Personally, I think the Composite UI App Block sucks! I've studied it intensely fro 6 months and MAYBE after about 6 months of studying, you MIGHT be able to put a project together. There is just way to much to grasp. One of our requirements at my company is to make a Framework that all projects can be built from. I would NEVER base this framework off of the Composite UI! I would be training developers for years! I understand that MS must make App Blocks which work for all cases and all scenarios. However, most of their naming conventions and the way they've put things together could have been done so much better and cleaner! One thing in particular is developing Plugins. If you use the Composite UI, not only will your Plugin need to know everything about the Host, but you Host also needs to know everything about your Plugin!!! :wtf: Decoupled model my a$$!