Symantec would never take if off their blacklist, hence my request to have a similar utility written. It should be a fairly simple program. I would think that someone could write some code that would inject a screenshot dll into the winlogon process on the remote machine and grab the screenshot and save it to the location requested by the commandline parameters. I just don't have the C programing skills to put it all together.
due to the nature of the program, it has ended up on symantec's black list. on your part, you can petition and convince symantec that it is not a malware. good luck. 
-lanux128