prospect 3.4.9 installed and runs like a dream on xp or vista/64 in CS3. if you can not get PHD to work for now in CS4. can't you either have First light as a seperate program outside of 3.4.9 or can't you just add it to 3.4.9 until adobe gets their act together? not sure why you had to change so much or deviate for the 3.4.9