I'm performing a series of tests right now with V4 with the S4 channels injected.  PoserPro 2010.  Easch result typed as it happens.

Test 1: Render of V4, basic settings (no IDL) no morphs injected, S4 basic texture.  No problem.
Test 2: V4, Morphs++ injection.  Morphs injected and work, no problem.
Test 3: Render of preceding.  No problem.
Test 4: S4 morphs injection.  No problems, all morphs work fine.
Test 5: Render of preceding.  No problems.
Test 6: Just for giggles, Creature morphs installed.  No problems.
Test 7: Deleted all lights, created a skyball with a texture, and rendered using IDL (low settings).  No problems at all.

Conclusion: y'all did something wrong.