We've migrated our win-application to IG 8.2. After opening form in designer and changing values of few properties in ToolbarManager or TabbedMdiManager uncompilable code is generated in file *.Designer.cs. This code is connected with FontData (but you don't need to modifcate values connected to FontData to see this code generated):
ApplyResources(appearance1.FontData, "appearance1.FontData");
ApplyResources(appearance1, "appearance1");
appearance1.ForceApplyResources = "FontData|";
If you edit this code and write "resources" before this line it will build without problems (e.g. resources.ApplyResources(appearance1.FontData, "appearance1.FontData"); ).
(It's not strictly connected with WinTabbedMdi, but I didn't know where to place it.)