Here you can download a font editor for Squeak 3.4. It sould also work for the earlier versions of Squeak 3.0 and 3.2 but it will not work for Squeak 2.7 and 2.8. The reason is that the layout of class StrikeFont and important parts of the text display machinery (namely class CharacterScanner) were changed with the introduction of Squeak 3.0.
A MVC project is needed to use the font editor, it is not usable in a Morphic project. (Sorry, but I still feel that Morphic is too complicated for me.) To use the font editor, you need "ThirdWay", my add-ons to MVC, that you can download here. Before you file in the file FontEditor.cs, you have to install "ThirdWay" from the change set tw.cs.
This is the font editor: You use the table view to see all glyphs of a selected font.
To edit a glyph, you switch to the glyph edit view.