Thanks for reporting this. I did some research and as it turned out, the problem was a banal one: I had used an old-fashioned dialog command to ask the user whether they really want to clear the values. Nothing to do with the glyph data.
The problem should already be fixed in the current version (beta 21, published on June 17).
If you still experience this crash then please let me know.
I am having troubles too using the Scaler. All versions are up to date and RMX have been working fine until recently… All seems to be working out until I hit the “Scale” Button, than Glyphs crashes…
Any ideas or hints?
And great tool btw… I even own a FL license