When I import the same font into GLYPHS, and then create an OT-file, everything is OK. Then I tried to import the OT-fontfile into FL, and then export it once again as OT. No problem.
So: Can I ignore the warnings from FL, or …?
Thank you for helping!
FontLab has a much older makeOTF build in. So the font might contain stuff that it can’t handle. And maybe you should ask at there forum? Why do you need to generate the font in FL and how did it got there?