Both M4 and V4.2 have a specific Muscle Morphs pack available from DAZ that give you control over actual muscles and groups. Looks like they're still available.

Also, if it seems like morph dials actually don't work (as opposed to just not liking the results), make sure you initialized your V4 and M4 after installation...they have an extra step that isn't common to most other figures that links the morph channels in the figure to the actual morphs you'll be installing.