Hi @Anonymous,
I started looking at your drawing file. I notice that many of the corners are constructed of plines which is a bit unusual rather than just using a FILLET command to make a nice curved corner that will connect to the straight sides.

I also noticed that much of this is just geometry rather than being blocks. The geometry is also not set to bylayer.
Ideally, you would create a block on layer 0 with properties set to Bylayer for each typical piece and then insert the block on the correct layer that already has a color assigned to it. I have done this for some of the chairs and for the sink.

Please take a look at my version and let me know if you have additional questions.
Please select the Accept as Solution button if my post solves your issue or answers your question.
John Vellek
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