So, you are using 27 materials with 1800x1200... that sounds pretty harsh to the cpu. Any other opinions?
You need to make sure you are properly managing the creation and destruction of materials. If you don't do it properly, your memory will build up like crazy, specially with this size of images. Another thing is try to reuse materials. If 5 cubes use the same image, dont create 5 materials, create only one and apply it to the 5 cubes. Thats all I can comment on. I'm not that familiar with lite, so I'd recommend looking for more opinions after you check what I say.
