The course seems fun, but I get tiny squares for some of the letters. Not all, but some.
Huh... maybe a font problem? It's lookin' fine here. If Cherryh is using some kind of font that your home system doesn't have, it'll substitute a different font, and the substitute may not have any character assigned for that ASCII code.
Anyway, here's the direct links (Cherryh changes filename styles):
http://www.cherryh.com/www/latin1.htm
http://www.cherryh.com/www/latin2.htm
http://www.cherryh.com/www/latin3.htm
http://www.cherryh.com/www/latin4.htm
http://www.cherryh.com/www/latin%205.htm
http://www.cherryh.com/www/latin%206.htm
http://www.cherryh.com/www/latin%207.htm
http://www.cherryh.com/www/latin%208.htm
http://www.cherryh.com/www/latin9.htm
http://www.cherryh.com/www/Latin_10.htm