no,
AH client include standard HTC skin pack
each terrain include your own skins pack, whichone replace standard skins. Client load skins from terrain and use same for every plane /every player flying this aircraft/.
Those skins are recorded in ah film recorded as custom from terrain.
Skins for MA, TA, DA are created and developed only by HTC crews.
For CT and SEA terrains are maked by terrain team or voluntiers. Skuzzy as HTC crew chk terrain and make him avilible for download. All that to prevent possibility of bugs and cheat.
U can build your own terrain and host him on H2H mode only.
If u wish to be helpfull for terrain creators contact with TE team, or Brady who coordinate CT terrains projects.
Since now is no possibility to use custom skins flying MA, mby in AH2
ramzey