remo2

Star Radiers was my favoritive video game and I want to play it on my Mac. I have download many Atari 5200 programs and I have the rom and I can get it to boot, but I can't turn on the Map, shields, computer. The only thing I can do is fire and start the engines. What programs for mac can I play Star Radiers on? What keys do I push, on a real Atari 800XL I press S for Shields I think G for map etc. Has anyone been able to play this game? Thanks, Remo