Thinapps Un Assign themselves after a Recompose. Why?

I have a particular pool in the VIEW 5.1.2 environment that when I recompose will not install the same thinapps that were assigned to it prior to the recompose.  When I go to VIEW the thinapp is no longer assigned.  Another weird thing is that there may be other thinapps assigned to the same VM and they are still there and installed on the VM.  Any ideas?