Only the lowercase italic version seems to be missing—it displays as the number 9. Uppercase, regular, bold, bold italic are all working fine for me.
Lowercase Eth is present in the Italic (version 0.81). How are you trying to enter it?
I’m entering text with Icelandic keyboard input. The problem persists in other applications like Microsoft Word:
I wonder if there’s a way to re-download the font?
The glyph is present in both Roman and Italic styles in version 0.80 on my system: