Hey Jamie
I'm involed in putting some fairly big lasers in UK clubs.
Most have audience scanning , with all necessary licensing and legal issues taken care of. I'ts not difficult , especially with a 300mW rgb.
Drop me a pm and I'll give you a number to call, and I'll talk you through it.
The first thing you'll need is some decent software. Pangolin , Medias are very popular. I sell Cypher , written by pangolin. All these will be several hudred quid, but worth it in the long run, especially if you wan to be safe.
Beware of free software with budget lasers !
Take it easy
Fluff