I cloned and tried to make tiles from the men's room tile (white with blue border), and they looked great in homecrafter, but were a dark purple in my game. At the time the only custom floor tile I had in my downloads folder was an indigo-tinted transparent floortile. I posted here and never got any response, but your problem sounds the same. I don't have GunMod's lighting hack, nor were they priced at $0. Sorry I don't have any answers.