Quote: "2) can the firing of the weapons be assigned to an energy function instead of cartridge? in this way the player will stop shooting when energy=0 and of course have a regeneration of energy?"
There is a script function called AddPlayerAmmo. I've never used this, but it seems possible that you could use this to add an amount of ammo at the start and then add more on a timer function. This could accomplish your goal.
Quote: "3) is it possible to assign functions to keys?"
What do you mean by functions and what do you mean by keys? If you mean keys as in keyboard keys, the base engine doesn't support any keys except E, but the Omega Core plugin I developed allows you to use all keyboard keys as well as mouse buttons.
System Specs: OS - Windows 7 Home Premium 64-bit SP1, CPU - AMD Phenom II X4 945, 3.0Ghz, RAM - 8Gb DDR3, GFX Card - 2048MB NVIDIA GeForce GT 640, FPSC-R Version - Beta 1.0071