Fonts change weighting during export - BUG

The most frustrating FCP bug I've come across which is making my job almost impossible.

I set a title to Bold/Semibold, everything is correct in the Viewer, but as soon as I click away from the title it jumps back to Regular/Light.

If I can get it to stick to the correct weighting in the timeline, then when I export the film, it exports in the wrong weight. Re-check the timeline, the font is bold, but on the export, the font is light.

I've seen reports that tweaking parameters on the fonts like tracking, and then resetting back to zero can fix this, but no luck.

Has anyone else experienced this, and found a reliable fix/workaround?

My client's brand font is bold weighting, so I literally can't do my job... HELP!