Hello everyone, long time watcher, first time caller. Driven insane and out of pure desperation i resorted to asking for help to other human beings. I'm in the process of making a custom improvement for my mod using Blender, following a very helpful guide posted on this forum. I might be on week 3 of the process at this point and about to give up. The model is a tree, the leaves are made by duplicating planes with an alpha channel and the texture on them,trunk and leaves are separate objects atm. At the point of unwrapping, following the suggestion to create a single UV map for the whole model, the leaves, which came already textured and sitting pretty, got absolutely scrambled, as they come with a preexisting Uv of their own, (wich i think might be an overlap of all the single planes). Since baking is the next step, and the guide doesn't mention how to handle multiple uv's or multiple textures how can i solve the problem? This is my first project with a custom model, and i am a newbie, so any kind of guidance would be a godsend (on texturing especially).Thank you, to anyone willing to take time to answer. I can provide any information you might need files included. 
