Doncha just love zbrush for editing
Yes the clothing uses panels. They are derived from extracting meshes from the main figure. I am still just messing around with them and so far they are pretty nice.
The straps and wraps are done in 3dsmax. I just made a duplicate of the main figure and deleted the 2 lower sub divisions then GoZed the dupe to max. In max I made the figure transparent and used polydraw to place poly strips on the surface. Using the shell modifier it gives the strips depth and also encloses them which is something zbrush seems to like.
Before I start the character I always unify the base stub mesh in zbrush so I am sculpting on the best size and then GoZ the base back to 3dsmax till I have the export settings in zbrush matching my preferred size in max exactly. Once I have that I save out the document as a project, but export setting will stay put with a tool save as well.
Anyhow once the strips are drawn and shelled I Goz back to zbrush then activate my figure in the menu, append the new strips and sculpt them using backface masking. That’s it really.
If you want fancy straps then the curve brushes will work magic. Since this is a quick block in it was just as fast to do little stuff like this in max.