For anyone interested here's the solution:
Uploader place inside callbackpanel in CustomFooterTemplate of Editor:
<div id="uploaderimg_div" style="display: none">
<eo:CallbackPanel ID="CallBackPanel2" runat="server" Triggers="{ControlID:AJAXUploaderImage;Parameter:Image}"
style="clear:both" ClientSideAfterUpdate="imgAfterUpdate" OnExecute="ImgUploadCallBack">
<eo:AJAXUploader runat="server" ID="AJAXUploaderImage" Width="250px" AutoUpload="true"
TempFileLocation="~/temp_upload" FinalFileLocation="~/temp_upload"
MaxDataSize="30000" MaxFileCount="1" AllowedExtension=".gif|.bmp|.png|.jpg|.jpeg|.tif"
ClientSideOnStart="uploaderimg_start" ClientSideOnDone="uploaderimg_stop" ClientSideOnCancel="uploaderimg_stop"
OnFileUploaded="AJAXUploaderImg_FileUploaded"
AutoPostBack="true">
<LayoutTemplate>
<table cellspacing="0" cellpadding="2" width="492" border="0">
<tr>
<td style="padding-top: 5px">
<eo:ProgressBar ID="ProgressBarImg" runat="server" ControlSkinID="Windows_XP">
</eo:ProgressBar>
</td>
</tr>
<tr>
<td>
<asp:PlaceHolder ID="ProgressTextPlaceHolderImg" runat="server">Progress Text Place Holder
</asp:PlaceHolder>
</td>
</tr>
</table>
</LayoutTemplate>
</eo:AJAXUploader></eo:CallbackPanel>
</div>
Javascript for ClientSideAfterUpdate:
function imgAfterUpdate(sender,data)
{
var oEditor = eo_GetObject('Editor1');
if (sender.getParam()=='Image')
{
oEditor.execCommand('InsertHTML','<img src="' + data + '" />');
}
else
{
oEditor.execCommand('InsertHTML','Error loading image');
}
}
Code-behind for OnExecute:
Protected Sub ImgUploadCallBack(ByVal sender As Object, ByVal e As EO.Web.CallbackEventArgs)
e.Data = String.Empty
If e.Parameter = "Image" Then
Dim Uploader As EO.Web.AJAXUploader = CType(Editor1.FooterContainer.FindControl("AJAXUploaderImage"), EO.Web.AJAXUploader)
e.Data = System.IO.Path.Combine(Uploader.FinalFileLocation, Uploader.PostedFiles(Uploader.PostedFiles.Length - 1).ClientFileName)
e.Data = e.Data.Replace("\\", "/")
e.Data = Uploader.ResolveUrl(e.Data)
End If
End Sub