"....now to find out how to create a joint controlled morph...lol"

That is easy. You do need ColorCurvators MorphLoader, though, to create a morph from a posed figure.

Let's bring V3RR's arm creases even lower with a JCM.

Step One:

Pose V3RR the way you want the JCM to be at 100%.

Step Two:

Export her via MorphLoader. Call the exported object V3RR-RAW.

Step Three:

Hide V3RR. (DO NOT MOVE OR RE-POSE HER !!!)

Load the V3RR-RAW object. (DO NOT MOVE OR RE-SIZE IT DURING THE IMPORT OR LATER !!!)