Here is one way to think about it: Once you have a character, use Spawn morph target to save a combination morph for each group involved. Save the CR2 as this character. Use these character morphs in a CR2 that only has movement, fix, expression, JC morphs. Remove the construction morphs. You many consider having a base CR2 with only these morphs in it and transfer the character morphs to a copy of it. V2 has several joint fix, and new facial expression morphs that would be good to include in the mix. So, to answer your question, there is no need to keep construction morphs from eith V1 or V2 once you have used them to create a character and have saved it.