Strange behavior - see attached. I think that the translation between mm in sketchup and m in enscape is not quite right: I had to change the texture to 20m wide so that it looked correct.
I never had problems with the scale. Might be same special case with that project. Can you send us the model for further investigation?
Does it look correct after you restart Enscape?
Onto another project just now - opened this one again and everything seems to be 100% - no sign of the problem seen above. Weird. Thanks - I'll know what to do if it happens again.