I've retested your original file.
The bad news:
It's difficult to make different library for different projects.
What could be good for one could be wrong for other.
In all the cases you will have a limited range of good view in SH3D plan view.
The good news:
If you print the plan as pdf you will have a correct view.
Let the program to choose the Best fit scale at first attempt.
In this way you could keep your 1mm thickness lines.
To use some colors it is a good idea but depend on who look at them.
You could add a legend with explanations to the plan.
PS I have to thank you because of you I've was forced to update the creation script.
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A computer program does what you tell it to do, not what you want it to do. Murphy's Law
When all else fails, read the instructions. Murphy's Law
If you don't like "AS IS", DIY. Dorin's law
