This is what divides bad levels from good levels. If you don't UV - map, it's like saying "i don't even care if my mod looks good". 

I forgot to mention, don't ever click the blue or yellow pin in sketchup, they only cause problems (the same problems the vertex editor causes without triangulating)

Fluidimporter:
http://www.fluidimporter.com/downloads/

BGM:
https://www.youtube.com/watch?v=5EcbHqMpTaM

another UV mapping technique by kinopio:
https://www.youtube.com/watch?v=QOoNGBPs06Y

another UV mapping technique:
https://www.youtube.com/watch?v=OQY-FBBWZkU