I completely understand, and I do apologise – it used to work so well, but from what I understand under the hood WordPress core changes have really messed it up.
Sorry to bring this up again but I have the same issue as @x-nilo. I was able to upload my custom fonts and I can select them but the font is still Times or whatever the default is. The fonts files are uploaded in individual folders in uploads>redux>custom-fonts>custom and I didn’t have to do this manually. I have the latest WordPress and theme installation.