прочитал в описании файла hhp:

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The CHM compiler extracts words from all the input files (those with .h in their names), converts them to lowercase and stores them in the $FIftiMain file.

Words in the leaf and index nodes are made up of the following characters stored as is: 0x01 (buggy), 0-9, a-z, _, 0xDE, 0xFE. Bytes from the input files are converted and stored as per the table below. Character entity references of the form ▼ are truncated to BYTEs and translated as per the table below. Character entity references of the form & are treated as whitespace, except for the the latin characters, which are converted as per the table below.
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Как можно настроить компилятор, чтобы русскиц текст был сохранен? Среди опций настройки файла справки ничего подходящего не нашел.

Здравствуйте, Petr_Fr, Вы писали:

P_F>прочитал в описании файла hhp:

P_F>-------
P_F>The CHM compiler extracts words from all the input files (those with .h in their names), converts them to lowercase and stores them in the $FIftiMain file.

P_F>Words in the leaf and index nodes are made up of the following characters stored as is: 0x01 (buggy), 0-9, a-z, _, 0xDE, 0xFE. Bytes from the input files are converted and stored as per the table below. Character entity references of the form ▼ are truncated to BYTEs and translated as per the table below. Character entity references of the form & are treated as whitespace, except for the the latin characters, which are converted as per the table below.
P_F>-------
P_F>Как можно настроить компилятор, чтобы русскиц текст был сохранен? Среди опций настройки файла справки ничего подходящего не нашел.

вообще-то он всегда правильно кодировал...

проверь у себя такие пункты:
— кодировка в HTML файлах из которых ты собираеш chm (META таг с енкодингои проставь)
— сетинги винды локальные (хотя как на меня это не должно влиять)