rlavalle - If the rotors are going to crack from heat stress it would be @ the slots first (since there is even less material).
Judging from the photos it's going to take awhile for them to crack. As mentioned, clean off the surface, bed the race pads in before the track day and you should be ok.
After the next track session, check to see if there's any of the pad residue on the rotors. Also check the pad as well for chunking. You may want to change to a Pagid pad or Ferrodo pad with a slightly larger heat range. (after your PF97's wear out).
Speaking of which, did you use the PF97's on the USDM OEM STi 1-piece rotors as well?
Also, when you installed the rotor, which way did you have the cooling veins pointed? These are directionally cooled, so it would make a difference as well.