1. get a dev console to load by finding out the nwjs version from the modify date and downloading the sdk so f12 would be unlocked,A true hero. Worked for me, game finally loaded after few seconds. How did you figure this and/or with zero moon out?
2. googled console error lines until i found a link to a post on zero moon page on f95 about that font not working on windows 7 but system.json didn't refer to the font here.
3. full text search for the font name until the css file came up.
from there i just used some random website to convert the font file to woff and edited the css file to use it.
making it use another font would have also worked.