yes. it's probably because you changed the drive.
no, you don't need Adaptec ASPI.
also, from the original thread on this registry hack, it seems you have to burn at least once before you can do this trick. only then does this registry key exist and then you can change it.
also, you changed the CDRW drive. in that thread you can read reports of some people that this trick didn't work for them. apparently it does not work on some drives.
One Ring to rule them all, One Ring to find them,
One Ring to bring them all and in the darkness bind them
In the land of Mordor, where the Shadows lie
M.C. Escher - Reptilien