checkin of myformat.sty.
Change "\renewcommand{\indexsubitem}{(...)}" to "\setindexsubitem{(...)}"
everywhere.
Some other minor nits that I happened to come across.
isn't likely to be of much interest these days....)
{\tt ...} ==> \code{...}
Added \label{module-blat} for the two supporting modules.
Added index entries for referred-to modules.