Due to a bug in Illustrator when dealing with compound paths, you might end up importing incomplete shapes, missing parts or weird overlaps in Fontself.
In such case, try to clean up your vector shapes:
- Start by applying the Pathfinder > Unite feature in Illustrator to merge all the shapes for a single character (you should turn on the Remove Redundant Points option in the Pathfinder's options menu to clean up extra points).
- If it still does not work, apply Object > Flatten Transparency with default settings.
In most cases, you should then be able to import your glyphs properly. If not, send us your .ai source file to firstname.lastname@example.org and we will have a look.