I'm using Windows XP SP2 32-bit.
I've also been using the old C::B for ages, and I had no problems updating to the new package. What I did was extract C::B itself from the archive over my old C::B, overwriting everything. I then removed my old MinGW installation and replaced it with the one from the archive. I didn't change anything else.
Mind you, C::B itself isn't the problem here, it's the updated MinGW that's acting up for you.