My last pic show your original Flexible txt w/ white background.
As long as the color if there are any in the drawing is "strong" they will turn black, pink, light green, cyan etc will be grey when printer set to Grey Tint.
And i asume you have color in different layers/ Objects inside the drawing, why else should you need to use Black only, there have to be something in color there.
Luckily i dont need to care anymore, here they accept more and more color as long the drawing are easy to read.
In my walls i use yellow and 80 % transparant in the wallstyles for framework, never had any issues about that.
We dont have printing cost as everything will be delivered electronic to building dep.
So the only thing i miss in TC is option for 3D brush on architect objects when it comes to similar to HL render, as it is a PITA if needed to do it manually, just waste of time.
But i dont keep my breath when waiting for that
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