[jonc2006]

some keyboards will only register a certain amount of key commands when they pressed at once (usually 2 or 3), so this is indeed a limitation of your hardware, not the emulator. if you want to fix this you need to buy a gaming keyboard as they often have no such limit.

 

[jonc2006]

that is one possibility, the limit could only apply to modifier, system or function keys but i cant say for sure.

 

[jonc2006]

yes its possible, just make sure you install the drivers for it. while i dont use one myself, there are a decent amount of other members here that do so you should be fine with it. you can also use it with other psx emulators if you ever want to switch to something else.