Example: I go into the aircraft selection menu. I click on the purple Jetranger, and click Details (or "OK", the result is the same). The preview shows a purple Jetranger rotating in the screen. I go back to the menu, and select the Highway patrol paint scheme, and click details. I see a highway patrol Jetranger in the window. Then I go back to the menu and select the plane white jetranger. I see the white jetranger in the window. So far so good, but now that I've selected the plain white jetranger, any other jetranger I pick will be plain white, whether it's in the details window, the selection window, or the sim itself.
This will happen with other aircraft as well, such as the F-18 Blue Angels #1, the white 737, the white 172, the white Beaver, the cargo DC-3, etc. And it's not just default aircraft.... This has happened on Dino Catteneo's T-45, on the livery with no tail letter. The one thing consistent is that it will get stuck on the aircraft that uses the base texture folder (not texture.1 or texture.red, etc.).
Sometimes it will go away after a while using a different aircraft. IE: the 172 gets stuck as white, but then I fly for an hour with the F-18, then the 172 might not be stuck. I figure the 172 texture that got loaded into memory got dumped during the flight, because the computer needed the memory for scenery or AI, etc.
It won't get stuck if there is a different model. For instance, I have three separate DC-3 folders, the default and two addons. The default variations will get stuck on the cargo livery, but if I select one of the addons, those will have their own liveries. Mind, these are in three completely separate aircraft folders. My guess is that even though they are based on the default DC-3, since the sim is opening a new aircraft folder with it's own model folder, it loads it as a new model, not knowing it's the same one.
I have also been able to trick the sim into not getting stuck. If I copy the model folder and rename it as model.1, and assign it to a repaint, the texture won't get stuck. Example: I copy the F-18's model, and rename it as model.1. In the aircraft.cfg file, I assign it to [fltsim.1], so now model=1 and texture=1. Are you following me so far? With this, all the F-18s will be stuck as Blue Angels #1, except Blue Angels #2, because BA#2 is looking at a separate model. It works if I make a model.x for each texture.x. However, it's a waste of time and hard drive space for something that is only a minor irritation.
The only other solution I've found is to exit the sim and restart, which is a pain when I want to compare paint schemes and browse my inventory.
