Personally, as I've said elswhere, I don;t like converted clothing! Strange things cna happen with it since the "child" groups still affect the "parent" groups, so if a shin is made dynamic it can have odd effects on the thigh group, hip groups can affect abdomen groups etc. So hybrid cltohing I design have a "ghost" group of one or 2 rows of verts seperating the dyanamic groups from the confoming groups. I also name my dynamic groups differently than the groups in the main figure, to avoid conflicts.

Hybrids that break up happen as a general rule if there are no matching bones in the skeleton. Even specific dynamic groups have to have a coresponding bone in the skeleton of the conformer. Also check the group elding commands to be sure your dynamic groups are welded to the correct conforming group. 

I agree with Cobaltdream, thought has to be put into the construction of the hybrid, makeing it as an after thought or conversion MIGHT give you decent results, or it might not. Making the clothing with Hybrid Dynamics as part of the design strongly reduces the potential problems.

I also wish E-Frontier would provide a file structure similar to the Material files in the Material Room where the setting could be save and loaded for the Cloth Room. This would go a long way to making the Cloth Room user friendly. Maybe some type of Mat (Dyn ?) Pose can be developed... I've just started look into what areas of the CR2 control the dynamics to see if this is a possibility but I'm not the most knowledgable person when it comes to CR2 hacks...

Still Hybrid Clothing can produce some really nice pictures and this is an area of Poser that deserves serious attention!

have fun,
mike