Not quite sure. Although I'm a DBP user, I could take some educated guesses.
1.) Are you running with the CD? If not, then try with it. Usually can only compile like 500 times without the cd.
2.) Is it a valid copy? I'm guessing it is, since you're already such an established developer. (Congrats on Tito widespread)
3.) You may have to re-install. (Make sure to back up everything!)
4.) Have you patched it down accidently?(1.13 -> 1.11) Not sure if this would effect anything, yet it's something to consider.
A book? I hate book. Book is stupid.
