Hyphen (minus sign) is OK. It caused a crash years ago in version 4.0 but finally got fixed.
See:
http://www.artlantis.com/plug-in-for-archicad-12_f-atl_import_us-1222.html
where it was \ / and * for that person. I do not know if there is a definitive list of things that work anywhere. (I believe the vertical bar | works - but it did not a few years ago.)
It might be some other geometric element. So, first, use a bold marquee to clip just a quadrant of your model, view in 3D and see if that will export. If yes, make a bigger marquee, etc. until you find the problem element. If no, make a smaller marquee, or perhaps display just walls, etc.
You may need to save a temporary copy of your AC file and then go into Attribute Manager and delete a bunch of materials to find what works. Once you find the problem, open your real file and correct things.
It is a frustrating thing to troubleshoot and work around whatever the bug is...
Karl
One of the forum moderators
AC 28 USA and earlier • macOS Sequoia 15.2, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB