Hello! I'm starting with the toolbar control and I decided to use the provided toolbar demo as a base. In design time everything's fine, but when I run the solution I miss the button images and background images. The rest of the css-properties seems to work.
I remark that I'm using the asp code as is, copy-pasted from the demo web page.

This is the asp code. There's nothing relevant about toolbar in code-behind.
    
        Code: HTML/ASPX
        
        <%@ Page Language="C#" AutoEventWireup="true" MasterPageFile="~/ASPNET/MasterPage.master" CodeFile="DatosPersonales.aspx.cs" Inherits="FOR_DatosPersonales" %>
<%@ Register Assembly="EO.Web" Namespace="EO.Web" TagPrefix="eo" %>
<%@ Register Src="~/CtrlsUsuario/MiTextBox.ascx" TagName="MiTextBox" TagPrefix="uc1" %>
<asp:Content ID="content" runat="server" ContentPlaceHolderID="cphMaster">
    <eo:ToolBar runat="server" id="ToolBar1" BackgroundImageRight="00100202" Width="400px" BackgroundImage="00100203"
	SeparatorImage="00100204" BackgroundImageLeft="00100201">	
	<DownStyle CssText="BORDER-RIGHT: #335ea8 1px solid; PADDING-RIGHT: 2px; BORDER-TOP: #335ea8 1px solid; PADDING-LEFT: 4px; FONT-SIZE: 12px; PADDING-BOTTOM: 1px; BORDER-LEFT: #335ea8 1px solid; CURSOR: hand; PADDING-TOP: 3px; BORDER-BOTTOM: #335ea8 1px solid; FONT-FAMILY: Tahoma; BACKGROUND-COLOR: #ffe1ac"></DownStyle>
	<HoverStyle CssText="BORDER-RIGHT: #335ea8 1px solid; PADDING-RIGHT: 3px; BORDER-TOP: #335ea8 1px solid; PADDING-LEFT: 3px; FONT-SIZE: 12px; PADDING-BOTTOM: 2px; BORDER-LEFT: #335ea8 1px solid; CURSOR: hand; PADDING-TOP: 2px; BORDER-BOTTOM: #335ea8 1px solid; FONT-FAMILY: Tahoma; BACKGROUND-COLOR: #ffe1ac"></HoverStyle>
	<Items>
        <eo:ToolBarItem CommandName="New" DropDownMenuID="Menu1:new" ImageUrl="00101001"
            Text="New" ToolTip="New" Type="DropDownMenu">
        </eo:ToolBarItem>
        <eo:ToolBarItem CommandName="Open" ImageUrl="00101002" Text="Open" ToolTip="Open">
        </eo:ToolBarItem>
        <eo:ToolBarItem CommandName="Save" ImageUrl="00101003" Text="Save" ToolTip="Save">
        </eo:ToolBarItem>
        <eo:ToolBarItem CommandName="SaveAll" ImageUrl="00101004" Text="Save All" ToolTip="Save All">
        </eo:ToolBarItem>
	</Items>
	<ItemTemplates>
        <eo:ToolBarItem Type="Custom">
            <normalstyle csstext="background-color:transparent;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;padding-bottom:1px;padding-left:2px;padding-right:2px;padding-top:2px;"></normalstyle>
            <hoverstyle csstext="background-color:transparent;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;padding-bottom:1px;padding-left:2px;padding-right:2px;padding-top:2px;"></hoverstyle>
            <downstyle csstext="background-color:transparent;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;padding-bottom:1px;padding-left:2px;padding-right:2px;padding-top:2px;"></downstyle>
        </eo:ToolBarItem>
        <eo:ToolBarItem Type="DropDownMenu">
            <normalstyle csstext="background-image:url('00100205');background-position-x:right;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;cursor:hand;padding-bottom:3px;padding-left:4px;padding-right:4px;padding-top:3px;"></normalstyle>
            <hoverstyle csstext="background-color:#ffe1ac;background-image:url('00100206');background-position-x:right;border-bottom-color:#335ea8;border-bottom-style:solid;border-bottom-width:1px;border-left-color:#335ea8;border-left-style:solid;border-left-width:1px;border-right-color:#335ea8;border-right-style:solid;border-right-width:1px;border-top-color:#335ea8;border-top-style:solid;border-top-width:1px;cursor:hand;padding-bottom:2px;padding-left:3px;padding-right:3px;padding-top:2px;"></hoverstyle>
            <downstyle csstext="BORDER-RIGHT: #335ea8 1px solid; PADDING-RIGHT: 2px; BORDER-TOP: #335ea8 1px solid; PADDING-LEFT: 4px; BACKGROUND-POSITION-X: right; BACKGROUND-IMAGE: url(00100206); PADDING-BOTTOM: 1px; BORDER-LEFT: #335ea8 1px solid; CURSOR: hand; PADDING-TOP: 3px; BORDER-BOTTOM: #335ea8 1px solid; BACKGROUND-COLOR: #ffe1ac"></downstyle>
        </eo:ToolBarItem>
	</ItemTemplates>
	<NormalStyle CssText="PADDING-RIGHT: 4px; PADDING-LEFT: 4px; FONT-SIZE: 12px; PADDING-BOTTOM: 3px; CURSOR: hand; BORDER-TOP-STYLE: none; PADDING-TOP: 3px; FONT-FAMILY: Tahoma; BORDER-RIGHT-STYLE: none; BORDER-LEFT-STYLE: none; BORDER-BOTTOM-STYLE: none"></NormalStyle>
</eo:ToolBar>
<eo:ContextMenu id="Menu1" runat="server" Width="200px" ControlSkinID="None" CheckIconUrl="OfficeCheckIcon2">
	<TopGroup Style-CssText="background-color:#abc7f6;">
		<Items>
			<eo:MenuItem ItemID="new" Text-Html="New">
				<SubMenu>
					<Items>
						<eo:MenuItem LeftIcon-Url="00101001" Text-Html="Document"></eo:MenuItem>
						<eo:MenuItem LeftIcon-Url="00030405" Text-Html="Folder"></eo:MenuItem>
						<eo:MenuItem LeftIcon-Url="00030402" Text-Html="Contact"></eo:MenuItem>
					</Items>
				</SubMenu>
			</eo:MenuItem>
		</Items>
	</TopGroup>
	<LookItems>
		<eo:MenuItem DisabledStyle-CssText="background-color:transparent;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;padding-bottom:1px;padding-left:5px;padding-right:5px;padding-top:1px;color:gray"
			Height="24" HoverStyle-CssText="background-color:#C0D6F4;border-bottom-color:#000080;border-bottom-style:solid;border-bottom-width:1px;border-left-color:#000080;border-left-style:solid;border-left-width:1px;border-right-color:#000080;border-right-style:solid;border-right-width:1px;border-top-color:#000080;border-top-style:solid;border-top-width:1px;padding-left:4px;padding-right:4px;padding-top:0px;padding-bottom:0px;"
			ItemID="_TopLevelItem" NormalStyle-CssText="background-color:transparent;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;padding-bottom:1px;padding-left:5px;padding-right:5px;padding-top:1px;"
			SelectedStyle-CssText="background-color:white;border-bottom-color:#000080;border-bottom-style:solid;border-bottom-width:1px;border-left-color:#000080;border-left-style:solid;border-left-width:1px;border-right-color:#000080;border-right-style:solid;border-right-width:1px;border-top-color:#000080;border-top-style:solid;border-top-width:1px;padding-left:4px;padding-right:4px;padding-top:0px;padding-bottom:0px;">
			<SubMenu ExpandEffect-Type="GlideTopToBottom" Style-CssText="background-color:#F6F6F6;border-bottom-color:#002D96;border-bottom-style:solid;border-bottom-width:1px;border-left-color:#002D96;border-left-style:solid;border-left-width:1px;border-right-color:#002D96;border-right-style:solid;border-right-width:1px;border-top-color:#002D96;border-top-style:solid;border-top-width:1px;color:black;cursor:hand;font-family:Tahoma;font-size:8pt;padding-bottom:1px;padding-left:1px;padding-right:1px;padding-top:1px;"
				CollapseEffect-Type="GlideTopToBottom" SideImage="Office2003SideBar2" LeftIconCellWidth="25"
				ItemSpacing="3"></SubMenu>
		</eo:MenuItem>
		<eo:MenuItem IsSeparator="True" ItemID="_Separator" NormalStyle-CssText="background-color:#6a8ccb;height:1px;margin-left:30px;width:1px;"></eo:MenuItem>
		<eo:MenuItem DisabledStyle-CssText="background-color:transparent;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;padding-bottom:1px;padding-left:2px;padding-right:5px;padding-top:1px;color:gray"
			Height="24" HoverStyle-CssText="background-color:#FFEEC2;border-bottom-color:#000080;border-bottom-style:solid;border-bottom-width:1px;border-left-color:#000080;border-left-style:solid;border-left-width:1px;border-right-color:#000080;border-right-style:solid;border-right-width:1px;border-top-color:#000080;border-top-style:solid;border-top-width:1px;padding-left:1px;padding-right:4px;padding-top:0px;"
			ItemID="_Default" NormalStyle-CssText="background-color:transparent;border-bottom-style:none;border-left-style:none;border-right-style:none;border-top-style:none;padding-bottom:1px;padding-left:2px;padding-right:5px;padding-top:1px;"
			SelectedStyle-CssText="background-color:white;border-bottom-color:#000080;border-bottom-style:solid;border-bottom-width:1px;border-left-color:#000080;border-left-style:solid;border-left-width:1px;border-right-color:#000080;border-right-style:solid;border-right-width:1px;border-top-color:#000080;border-top-style:solid;border-top-width:1px;padding-left:1px;padding-right:4px;padding-top:0px;"
			Text-Padding-Right="30">
			<SubMenu ExpandEffect-Type="GlideTopToBottom" Style-CssText="background-color:#F6F6F6;border-bottom-color:#002D96;border-bottom-style:solid;border-bottom-width:1px;border-left-color:#002D96;border-left-style:solid;border-left-width:1px;border-right-color:#002D96;border-right-style:solid;border-right-width:1px;border-top-color:#002D96;border-top-style:solid;border-top-width:1px;color:black;cursor:hand;font-family:Tahoma;font-size:8pt;padding-bottom:1px;padding-left:1px;padding-right:1px;padding-top:1px;"
				CollapseEffect-Type="GlideTopToBottom" SideImage="Office2003SideBar2" LeftIconCellWidth="25"
				ItemSpacing="3"></SubMenu>
		</eo:MenuItem>
	</LookItems>
</eo:ContextMenu>
    
     
    <asp:UpdatePanel ID="upaDatos" runat="server">
        <ContentTemplate>
            <div style="width:500px;background-color:#E0E0E0;text-align:center;">
                <asp:Button ID="btnAgregar" runat="server" Text="INSERTAR" OnClick="btnAgregar_Click" />
                <asp:Button ID="btnActualizar" runat="server" Text="EDITAR" OnClick="btnActualizar_Click" />
                <asp:Button ID="btnAceptarAgregar" runat="server" Text="ACEPTAR" OnClick="btnAceptarAgregar_Click" />
                <asp:Button ID="btnCancelarAgregar" runat="server" Text="CANCELAR" OnClick="btnCancelarAgregar_Click" />
                <asp:Button ID="btnAceptarActualizar" runat="server" Text="ACEPTAR" OnClick="btnAceptarActualizar_Click" />
                <asp:Button ID="btnCancelarActualizar" runat="server" Text="CANCELAR" OnClick="btnCancelarActualizar_Click" />
            </div>
            <br />
            <asp:UpdatePanel ID="upaDetalleDatos" runat="server">                                
                <ContentTemplate>
                    <uc1:MiTextBox ID="mtxtNombre" runat="server" /><br /><br />
                    <asp:Label ID="labArea" runat="server" Text="AREA"></asp:Label><br />
                    <asp:DropDownList ID="ddlArea" runat="server" DataSourceID="odsAreas" DataTextField="Texto" DataValueField="Valor"></asp:DropDownList><asp:ObjectDataSource ID="odsAreas" runat="server" SelectMethod="DevolverTGU"
                        TypeName="TGUCls">
                        <SelectParameters>
                            <asp:Parameter DefaultValue="AREAS" Name="strTGU" Type="String" />
                        </SelectParameters>
                    </asp:ObjectDataSource>
                </ContentTemplate>
            </asp:UpdatePanel>            
            <br />
            <asp:Panel ID="Panel1" runat="server" Width="500px" style="text-align:center;">               
                <asp:GridView ID="grvDatos" runat="server" AllowPaging="True" AutoGenerateColumns="False" 
                    PageSize="20" Width="500px" DataKeyNames="Código" DataSourceID="odsDetalles" OnSelectedIndexChanged="grvDatos_SelectedIndexChanged" OnPageIndexChanged="grvDatos_PageIndexChanged" >                                                          
                    <AlternatingRowStyle BackColor="#E0E0E0" />
                    <PagerStyle Wrap="True" />                    
                    <SelectedRowStyle BackColor="Red" ForeColor="White" />
                    <Columns>
                        <asp:CommandField ButtonType="Image" SelectImageUrl="~/img/ARROW_RIGHT_GREEN.png"
                            ShowSelectButton="True" />
                        <asp:BoundField DataField="Código" HeaderText="Código" ReadOnly="True"
                            SortExpression="Código" Visible="false" />
                        <asp:BoundField DataField="Nombre" SortExpression="Nombre" />
                        <asp:BoundField DataField="Texto" SortExpression="Texto" />
                    </Columns>
                </asp:GridView>                
                <asp:ObjectDataSource ID="odsDetalles" runat="server" SelectMethod="DevolverDatosPorArea"
                    TypeName="DatosPersonales_RN"></asp:ObjectDataSource>
            </asp:Panel>
        </ContentTemplate>
    </asp:UpdatePanel>
</asp:Content> 
     
 
Thank you very much and best regards
EDIT: When I use regular images (I mean, images that are stored in a png or jpg file), it works fine. It only fails for built-in images, like "LeftIcon-Url="00101001".