Default SPV C550 to Qtek 8200 ROM

Ok, so I tryed to run this Qtek ROM update program which is Russian, so I could turn my Orange SPV C550 into a non-branded device.

At first everything was going well, then I got to this nice screen telling me the software wasn't suited for my phone. The phone got stuck in the three color screen, but when I disconnected the battery and put it back in, and turned the phone on again, fortunately it still was functioning...

But now the big question, how can I get rid of everything Orange put on the phone? And end up with a nice non-branded phone?

Are there more steps needed to loose everything on the phone (don't really care about a back-up)? Is there any way to do this at all?