Hi,
Try changing this settting in Web.config:
<customErrors mode="RemoteOnly" defaultRedirect="Error.htm" />
change it from "RemoteOnly" to "Off" and then when an exception happens it should display it instead of just logging it and going to the generic error page. Maybe or maybe not more error detail will be shown.
Let me know if it provides any more specific error information.
Hope it helps,
Joe