i've noticed there seem to be font issues.
 
i don't know if you've tried these, but they're what we use in my 'icelandic manuscript reading' class at the university. Reykjavík Times has most of the characters, while Akureyri is a collection of rarely used symbols. you can get them on this url: http://www.hit.uib.no/menota/guidelines/tools/fonts/fonts.html (there are other sorts here too, but we use Reykjavík and Akureyri, they're made specifically for using with icelandic manuscripts)
don't know if everyone can use them.. but if most people have the same font installed, won't they then see it when others use it?
i'm NOT a computer person, not at all, but i thought it wouldn't hurt to send it.
 
berglaug