If you just want to show the extents of your upper floor slab on the ground floor then in the settings for the upper floor slab you will want to have a look at the "Show on Storeys" settings.
Try setting it to "show on home and one storey down".
The only control the line type (dashed, solid, etc.) is set in the OPTIONS menu > Project Preferences > Construction Elements...
You don't have any control of the pen colour (separate to what you see in the upper floor).
Barry.
One of the forum moderators.
Versions 6.5 to 27
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