Hey,
I haven't got the answer for your problem but maybe I can point you in the right direction. I don't think you would be able to do a bullet hole by script, I think that it would have to be an addon so it is an object. Then can it can be called by a script somehow. The only other thing I can think off (with my very limited OFP knowledge) to do with a script, might be the particle engine. Maybe after a lot of arsen about, you could do a small dot (that would look crap up close) using that sort of stuff. Another problem could be calling it when you hit objects, the different angles it would have to work on would also be a drama, I have no idea. Just thought it might help.