Attached is the first draft of my AP system for BRP. It's fairly simple but adds a bit of book-keeping to combat. This is very much in its's early stages so I'll upload revisions to it as I find problems (or others do).
The idea behind it is to open up more tactical options and make combat more dynamic. If you played X-Com, Jagged Alliance or Silent Storm then you should have some idea what to expect from it.
It's primarily written with my Hard SF game in mind so you'll probably need to tweak some of the details to make it fit for other games but I've included a few optional sections for those that want to add more detail or account for factors that I've ignored.