Glenn, there is no /q switch but that's basically because KiXtart is not a batch file and we wouldn't really be interacting with it.

I've had a few e-mails and posts here with Ruud on this issue and it should work just fine, but it doesn't. Thus it is a bug (IMHO)

RD /S (fixed for 4.53) should remove all. I just never tested the exact same way as here.

RD "FOLDER" /S should remove everything regardless of file/folder attribute.