Texture map : 4096x4096 (BMP and TGA) Normal map : 4096x4096 (TGA) NO NORMAL MAP APPILED ON PREVIEW PICTURES OR TURNTABLE!
The ZTL file has 6 subdivision levels. Preview renders are low res (1200x1200). As you know the obj files are compatible with almost every 3D applications. The preview files rendered with Octane Cinema 4D plugin (day light) on Cinema 4d. If you need an extreme decimation please contact with me. I'll help you happily free of charge. If you like Andria, you may search for her sisters Fusia, Mia and Asia under name 'Mia and her sisters'.
ps: If you try to open any of obj files on ZBrush (I suggest not. Because you have already the ZTL file.) Don't forget flip the texture vertically.