If you download the latest version of JassNewGen it comes with the UMSWE package. This package gives you some extra options in the "Game Interface" window which can be found in the "Advanced" tab
Make sure the "Enable UMSWE" option is clicked when you do this or they won't show up
If they still don't, just restart JassNewGen and they should be there.
Simply import your font, then copy and paste the path into the font options into the "game interface" window
hope this helps!
- CW