Hi Fran, STEP format is a bit tricky with colors, there are 2 different sub variations of STEP format, and the sort of main original structure (AP203) just does not have any mechanism in it for representing colors.

So that's not a particularly unusual thing for colors to just not come through with STEP format in general.

There is a different variation called AP214 I think which then adds things like colors, I think MoI will read in one of those but won't generate one of those for export currently.

I'll check with the author of the STEP library that MoI uses and see if it can be configured to write out AP214 or whether that's not supported currently.

I'm not sure if writing AP214 by default might cause other problems though since it seems that often times the original AP203 structure seems to be considered the normal one used for mechanical CAD data transfer.

Anyway that's why it's a somewhat tricky issue, because the main original STEP format itself just did not include any method in it to store color data.

- Michael