In the drawing formats some lines and dimensions are grey whereas some are black; that transfers on paper as well and the gray print is hardly legible.
Is there an explanation for those differences in colour and how can this be overcome?
Reference (or redundant) dimensions are automatically shown in gray by default. You have to go to Tools>Options>SystemOptions>Colors> and go through the list. It's probably under Dimensions. Many of the names are rather cryptic, so play around. Most don't need to be changed.
When you're making drawings you will spend a lot of time in Tools>Options>SystemOptions and Tools>Options>DrawingProperties to get the drawings to look right.
The previous reply is correct. The setting is under Dimensions in System Options. I would recommend changing your color of non-inserted dims to a dark gray. That way, you can still tell the difference between inserted and non-inserted dims, but it won't be obvious to other people reading the drawing when it is printed or PDF.
I wrote an article about that here:
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