How to make Banners & other mod making questions

[Hoplosternum]

My multiplayer scenario is nearly done. Just a few last questions if anyone can help.

In order to make a mod banner what do I need to do? I know where it goes and where to put this address in the mod file but how do I make the file i.e how do I get a .tga file? I have MS Paint, irfanview and CoralDraw. I don't seem to be able to even open a .tga with these never mind make one!

I have put in some recruitable commanders that are pretty tough. Ideally I would like to limit the number of these but still have them bought from the Capital. i.e. I want to make them Unique and limit them to say 6. Is it possible to do this and if so how?

If I create a recruitable unit (not a commander) that has magic paths, summon allies and auto summons and other abilities that are useable only by commanders will any of these take effect before the unit is Gift of Reasoned? And is autosummons commander only? Or will a unit spawn other units when not a commander? I assume it will acquire these abilities once it is Gift of Reasoned.