What’s most important to know is that Fixedsys Excelsior will only display correctly at 16 pixels, which is the same as 12 point on a PC. On a Mac, you may not be able to see Fixedsys Excelsior correctly except in software which allows you to specify text-size in pixels. And if you don’t see the font installed under ‘F’ in your fontlist, look towards the bottom of the list where the software might place non-Latin fonts.

Basics / FAQ
Scripts: Information & Examples (as an image)
Scripts: Information & Examples (as text, if you have installed the font already)
Opentype Support