When converting to ASCII, Pure C Help, ST-Guide or Manualpage UDO can generate a relative regular right margin due to its semi-automatic Hyphenation.
The right margin becomes irregular when long words haven't enough place at the end of a line. UDO will print a warning containing the specific word and you should try to insert some Hyphenation marks.
Hint:
The command !sloppy switches of these warnings, !fussy switches them back on. While developing a documentation you should use !sloppy. At the end of developing a text you should comment this switch and you should look after warnings according short lines.