Programming Office Business Applications (OBA) with VSTO is an extreme -you are don’t ever know, which COM wrappers are realized and work good, and which are not. I have some experience with Bookmark control (included in VSTO 3.0 SP1), which is confirm it :) I need to do anything in Word 2007 like Intellisense in Visual Studio. User types a few symbols, and Word show the list of variants, which contains in the internal reference book of my app. But small search at MSDN forums help me understand, ......