No, Freehand MX does not support OpenType features, so the only way is to open your typeface in a type design program and generate an alternative version like you were forced to do with Type1.

I'm not sure about Unicode support, either...

Hmm, I think it

fi and fl ligatures are normally part of the standard 256 character set, that's why you can access them with key commands. That works for all types of font formats, as long as the font includes a full character set, that it.

Other ligatures are not typically found in the standard character set, which is what makes unicode and opentype so appealing for the user.

Many larger, older font families had alternate, or expert fonts that you could buy extra(like Adobe Minion, for instance). This special font had 30 characters or so, many of which were cool ligatures. OpenType allows these to built into standard, single fonts.