that is the only general solution
perhaps it doesn't use the control port
there may be other hacks you can do, like telling windows to launch vidalia as a different user, but you may still need to disable the S_DEBUG credential (or whatever it is, I forget) for content watch still
maybe get it to launch content watch as a different user is better. but it sounds like you're not able to change content watch's behavior for some reason?
oh actually you may be able to use TorVM