I'm not seeing any problem on the demo site with IE 10. I downloaded the 2 files you had uploaded in shared files then deleted them from shared files and uploaded them again with IE 10 and had no errors.
I do know that there does exist an IE 10 bug when using imagebutton inside update panel it will throw an error under .NET 3.5 or 4.0, but the bug is fixed in .NET 4.5. The demo site has .NET 4.5 so the bug does not exist there. The Shared Files does use imagebutton inside updatepanel so if not using .NET 4.5 you can get errors.
I recommend use .NET 4.5 hosting and if the problem continues after that check the mojoPortal log for errors about the upload.
Hope that helps,