i know nothing about git but after reading your post i went and downloaded the latest version from the official site and watched 1-2 tutorials to see what is about. if it's smth important i'll try to get the hang of it but it might take days.
wouldn't it be easier (n probably quicker

) if you could make the changes in the dll and then upload it as a compiled dll every now and then so that i could do some testing?
Maybe, but I would regret it if something goes wrong as git is excellent in keeping track of changed lines, hence it highlights when I change lines I shouldn't have touched. I could make a project for you on sourceforge and add git to it. It shouldn't take me long as I tried it before. However to do that, I would need a name for the mod and it doesn't look like you mentioned one yet. I would also need to add your sourceforge account to people with write access, though that doesn't strictly have to be right on project creation. As I often mention, using git or similar makes it a whole lot easier to assist when some modder runs into a problem and it is possible to run into problems even if the changes are in xml only.
One file I know I need right away is
GameFont.tga. You mentioned you added an airport icon. Naturally I can't test if it shows up unless I have it, but more importantly I need the file to see where you placed it. The game translates each location to a number and the number is needed to print the icon. Naturally without the location I can't figure out the number.
Also speaking from experienced, the git client which seems to cause the least problems for git-newbies appear to be
smartGIT. The interface is quite simple and people usually figure it out in no time. Some people recommend
tortoiseGIT, but I find the integration with explorer confusing as it isn't always clear when you do something in git to explorer. Also while tortoiseGIT can handle most mods just fine, it can't handle M:C as it fails to use the submodules correctly. I know submodules is an advanced feature and overkill for most mods, but I would expect a widely used git client to support the feature, but it seems that I assumed wrong. SmartGIT handles M:C just fine.
Also for git client recommendations I completely ignore non-free clients. SmartGIT is free for non-commercial use, which includes modding.
same goes for me ofcourse. i will upload the units as soon as i finish editing them so that you can check them ingame or with nifscope for errors, suggestions, etc. if you want me to, i could just upload the unit (including all the movement files ofcourse, it would be a complete unit, "add n play"

) or the unit plus the blender files (size might be a little big, depending the work cause i like to save every few steps of the work).
That sounds fine. Well except for the file size, but I do understand why you save often and I likely would do the same.
Isn't there a way to shrink files made in blender? It doesn't sound right that saving 5 times makes the file bigger than if you just saved once. If it saves some change history, then it should be possible to strip that data to get small files, right?