Fonts that are included at compile time are hardwired and cannot be changed. This takes place automatically at precision 2. The only fonts which currently contain ligatures are the Roman Complex, Italic Complex, and Cyrillic Complex fonts. The K and H here are both capitalized since they are both part of the first character. All sizes of all fonts are aligned together by their baselines.
Horizontal alignment is based according to the beginning and ending horizontal positions.
You can use marks to make the ending position be anywhere in the string you wish. The last printable character in a string is the character centered on as the symbol. Size changes and horizontal shifts are taken into account in the symbol justification mode, but shifts up and down are not. Which glyph is used for this is installation dependent, and is set by defines in gentext.c. An error message will be produced the first time that a nonexistent glyph is referenced.