unlike Crispin i havent been so succesful yet. I have tried the same with my regular paper and developer but i think the light i use for flash is too strong. I only have limited place so its about 2 feet above my tray. I'm using a 25 watt bulb, but will get something less. I have hooked the bulb up to my timer, but the shortest i can get there is 1 second. The best (or not soo bad) result came after developping for 1,5 minutes, flash for 1 second and then taking the print out almost immediately. If i leave it in longer it goes almost black.
i'll try again and let you know