I can help with a couple of these
1- The pilot body is currently beign reworked, it will come back sometime soon (hopefully)
3- I'll try to explain as best as I can:
- The countermeasures controls are on the right side panel, below the IFF controls (from the front to the back you'll find INS, then IFF, then the countermeasures).
- The CM panel has two sections. On the left side you have a knob and three switches that control ECM, RWR and D2D. On the right side of the panel you'll see a three position switch labeled LL and a big knob with 11 positions.
- You'll want to set the LL switch to S.A. "LL" stands for "Lance Leurres", which means "Decoy Dispenser". "S.A." means "Semi Automatic", meaning pilot command is required to launch decoys. Automatic mode is not implemented, IIRC there is no public info on how it works.
- You have to select a decoy program using the big knob. Position "A" stands for "arrêt", meaning "off". You can see what each program is on your kneeboard, in general they are different amounts of chaff/flares launched. You should set it depending on expected threats.
- To activate the decoy dispenser and execute the selected program, you use a button on your HOTAS. The name of the control mapping is "Decoy Program Release".
- You also have a panic button in you HOTAS that releases a special program consiting on a bunch of chaff and flares in case of emergency.
Be aware that the Mirage is rather limited in flares count, so use sparingly. There is a box sitting on top of your dashboard to the right, with indicator lights that let you know if you are launching decoys and if you are running out of a particular type. There is no way to see exactly how many are left.