Open the leaf file in the VM and then use the UVMapper to adjust the texture. Save the file and restart C; open your tree file and then apply the texture map to the 'leaf' layer in the layers list shader. I don't think it's possible to put separate texture maps on the top and bottom of the leaf. You can add thickness to the leaf and give the top and bottom different shader domains but these aren't available in the tree shader. There may be a way but I couldn't get it to work. The simplest way is the make your 'leaf' a collection of leaves, then apply a single texture map showing different sides for different leaves. HTH