Gas BB pistol info/help

[SGTSNIPER]

Although i have had a tac master in the past i never really used it other than target shooting, I now however am getting a WE High Capa 5.1 Full Metal Version..Being thick towards gas pistold im in need of a little help,
1. would these extras fit. G&P Tactical 20mm R.I.S. Mount for M92F, Laylax (Nineball) High Capa Recoil Spring Guide and High Speed Spring 7" (is the spring just a replacement spring or does it affect the workings in any way? ie more recoil/ softer recoil?) (as sold on Z1)

2. what cosmetic extras are available for it.

3. what type of gas

4. i have seen guys with gas pipes attached to there mags, 'like lanyards' but feeding gas to the mag, are these available for this type of mag as ive only seen them used on beretta's..?

all help appreciated. cheers mark