V2

Thanks, Galane. You've saved Christmas (for me anyway). The adapter tanks didn't have textures at first but that's because they where dependent on the Mk3 cockpit being where it was supposed to be in the GameData\Squad\Parts\Mk3 folder. I soon sorted that out by throwing everything in propulsion. I'm a bit weak with my Kerbal-fu lately. I haven't really had time to mess with modding the game for a year and half. That's ancient history around here.

Yeah I'm interested in such a guide too. I'm trying to do the inverse though, backporting the new Mk3 parts to 0.25 so I can actually use them. The new cockpit shows up fine if I put it in GameData\Mk3\Mk3Cockpit_Shuttle but the load screen hangs up without crashing on the 100LFO tank when I put it in GameData\Squad\Parts\Mk3\Mk3Fuselage. Placing it anywhere else will get KSP to load and run normally but, the new Mk3 fuselage parts are nowhere to be found. The cargo bays do work from GameData\Squad\Parts\Mk3\Mk3CargoBay so it's something peculiar to fuel tanks' cfg files. I'm assuming those cool Mk3 adapters are also fuel tanks. I have no way of knowing myself right now because 0.90 is D.O.A. for me. I don't care though, without the new atmo dynamics I see little point to 0.90 beyond the Mk3 parts.