After painting with createx paints should I use a clear coat and light sanding before the envirotex? If so what would you recomend?

You don't need to. Createx and Envirotex work perfectly together. Unless you need to knock down any bumps or bubbles, you shouldn't need to sand either.

If your going to assemble the plug after painting, and before environtex, you may need to put a clear coat on to protect the paint from oil etc. on your hands. Then you would use a fine scotch brite pad over the clear before the epoxy. If you assemble after epoxy avoids alot of problems, but some guys like all the hardware epoxied together with the
plug.
Do a search under clear coat to find what guys use.