Online / Silverlight api app

[JimBridge]

I have a Silverlight  web app we run normally from maps hosted on our ArcGIS server manager.  I uploaded the map to ARCGIS online by zipping the layers and uploaded. Online I can see all the layers and display the map correctly. When I connect my application I can connect and it seems to be running correctly but I'm not seeing the map images. I'm just getting a gray screen but am seeing the scale etc. When this has happened locally its been incorrect or missing ClientAccessPolicy and Crossdomain files or access to the output directory. I'm not sure how to debug this on when running from ArcGIS online.
Any help would be appreciated.
Thanks
Jim

[JimBridge]

In looking deeper it looks like it could be an http vs https issue. I get a mixed content warning in ie when I start my app. It is running under https and the ArcGIS.com  feature service is coming up https. In fiddler everything seems to be showing as protocol http with an url going to the 443 (https) port.

Not sure why I'm getting the mixed content.

[JimBridge]

Using fire bug I'm seeing this :

"NetworkError: 400 Bad Request - https://services1.arcgis.com/JFJ44y4hkNP2Js0i/ArcGIS/rest/services/Parcels/FeatureServer/export?bbox..."