Save broken — how to import masters?

Hey Folks,
pardon if this is a very obvious Question:

Recently one of my Saves broke (crash on load),
but I have the Results in the (two) exported font-weights.

Is there a way I can import the one weight as the “light” variant of the
other one?

Can you send me the broken .glyphs file?

Open both files and theyou can merge them in font info > masters > gear button in the lower left > add font.

Sure, wich way you want it?
I can not upload it zipped, i.e

The preview shows that something with the letters has gone off,
as far as i know it worked properly last save.

The merging worked, but other than in the glyph file the path is not
in the right direction / masters aren’t nicely compatible as it was before.

You can send it to support (at) (this website without www)