Fonts can be a pain.
I'm pretty sure it's a very crude recognition method, literally comparing pixels. So similar isn't good enough, unfortunately.
If you've chosen a font you think should work, you can get more info by clicking on the ""show character"" button in region editor. You can see which characters aren't matching. Make sure that the region is the correct size, and the vertical positioning is consistent.
Worst comes to worst you'll have to merge characters into an empty/similar font.
If you can find a decent third party font analyzer that would be a big help. (Post it on here if you do)
If you figure out that it's a font that isn't included by default, you can import it through ""System Manager""->""Fonts""
Good luck!