VSTO Differences in VS2010 RC1

Yesterday I restarted working on an Oulook Add-in I'm cooking up for Office 2007 that I began developing in VS2010 Beta 2, and I got pissed when the code that was running quite well, simply gave me compiler errors.

Well apparently there were some changes from Beta 2 to RC 1 regarding the development of Office add-ins.

The main problem, for me, was that the class Microsoft.Office.Tools.CollectionBase<T> is gone so, any class that derives from it needed to be updated manually, and the affected classes were ThisFormRegionCollection and WindowFormRegionCollection that were changed from being a derived class of CollectionBase<Microsoft.Office.Tools.Outlook.IFormRegion> to be a derived class of Microsoft.Office.Tools.Outlook.FormRegionCollectionBase.

After changing this the code was recompiled successfully.