I think you'll find the best bet is to get access to a copy of Max Hundleby and Rainer Strasheim's "A7V...and captured british tanks" book, done for Foulis some years ago.
With respect to everyone here, I don't think answres to your questions via the list can do justice to the wealth of information on teh Mk Ivs this contains, and I'd strongly advise you not to try to do a Beutepanzer without reading it carefully. The book contains full organisational details, photos, action reports and camo details.
I made some notes on the topic as part of my series on WW1 tanks in Tankette, and you'll find good details on German camo, from primary sources on the rather terrific Landships site. Link for Amazon and summary biblographic details: