Maybe you should just run it as a licensed application with the serial number provided by Adobe? Technically, it's not really a trial version.
serial number required!
Important: In order to activate the Flash Catalyst beta and use the product beyond the default 30-day trial, you will need the appropriate serial number:
Excellent. Thanks. Never even noticed that note below the link.
I have similar problem, installed ok after putting in the correct serial, but when I attempt to run it prompts me for a serial number (or trial which is expired - went from 30days to 0 days just from relaunching). When I put in the correct serial # (it gets the green tick) and press 'continue', the window closes and then just reopens again. Have attempted reinstalling to no avail... have flash builder beta 2 installed with no problems with a valid license as well.
hmm creating as a new question, pls ignore.