Ok-Minitutorial
1)when you are sure to have set your model measures to cm, make a box size of 253x253x253. To do so, use the square tool, draw any squre and right after drawing (don't do anithing else between) input 253;253 these must appear in the ValueControlBox (VCB) in the lower right corner of the program window. Pres return, the square should resize to the input dimensions.
Take the pushpull tool, pull the square up and without further actions, input 253 the result must be a box of 253x253x253, verify it with the tape measure tool.
2) delete the ceiling and 2 adjacent wals so you have an open box the size of a segment in fpsc. Group, lock and use as a reference for your model size.
One more cool tip: when you press ctrl while measuring a distance with the tape measure, you can input any value right after measuring and Sketchup will ask if you want to resize the whole model according to this value...neat if you have a complex model on the wrong scale or like to model on a larger scale and resize afterwards.
I am Jacks complete lack of surprise.
