Is it possible to give rockets ambient sound when they fly like in Quake 3? 

I don't really have any idea how to do this (tho i think i saw 1 or 2 old mods do this?)

1 how do i make the player start with a spawn menu when they first spawn into a map?

2 and then how do I make them spawn as a monster?

3 and how do i make them control the monster? 

These are some fairly sophisticated questions depending on your expereince with QuakeC and programming in general.

I certainly can't show you how to do these in a forum post but others probably can. But the good news is all or most of these are available as tutorials on this hideously ugly but infinitely helpful website. 

Does anyone know any of those old mods where you can play as a monster selected from a menu, and it includes the scr qc in the download?

Or how to decompile their progs.dat?

I think if I take a look how they did it, would help!