@Jim...yep that's what I do (apart from the re-saving) Load the existing 3/4 tune, but I want to hear how it sounds in 4/4. But when I load the 4/4 it still plays in 3/4.
Is it the actual saving and re-opening that does it? If so, that's a bit clunky...measn I have to save several versions instead of just auditioning changes first. I guess I could do it in the style picker window using the "Use Chords Of song" option...didn't try that yet.