From this error that is logged whenever the app recycles:
2010-06-01 10:20:35,293 ERROR mojoPortal.Web.Global - Application_Start Could not register VirtualPathProvider, this error is expected when running in Medium trust or lower
System.Security.SecurityException: Request for the permission of type 'System.Web.AspNetHostingPermission
I can tell that you are running under Medium Trust so the NeatUpload component cannot function and it falls back to normal ASP.NET file upload.
Then this is the error when you upload a file:
2010-06-01 10:20:46,993 ERROR mojoPortal.Web.Global - 172.16.10.120-en-US - /Dialog/FileDialog.aspx?ed=fck&type=file
System.Web.HttpException: Maximum request length exceeded.
It means the file being uploaded is larger than allowed by configuration. You should be able to solve that, look for this in a commented out part of Web.config:
<httpRuntime maxRequestLength="2097151" executionTimeout="3600" useFullyQualifiedRedirectUrl="true" />
and uncomment it to make a larger max request length allowed.
Hope it helps,