There’s a README file included with the project which explains all of the file names. I haven’t used the term “forced” in years, so I think you have a very old version. I sent you a link to the current version.

Summary of the meanings of the various filenames:

mono: indicates subtitles designed to accompany the unique dialogue in the mono mix
SDH: indicates subtitles designed for the deaf and hard of hearing
full: everything is subtitled
titles (previously forced): only onscreen text is subtitled, to accompany a dub that does not voice over the onscreen text (and/or alien languages)
native: no onscreen text is subtitled, designed to accompany video that already includes burnt-in alien subtitles
nocrawl: the opening titles and crawl are not subtitled, typically designed to accompany video that does not include burnt-in alien subtitles
match: same as native, but designed to mimic the appearance of theatrical alien subtitles
alien-35mm: subtitles for alien dialogue only, taken directly from 35mm film elements
alien-reconst: subtitles for alien dialogue only, rendered to look almost exactly like reference images of the theatrical alien subtitles
template: used only for creating new subtitles
compat: indicates that the text is specially formatted for broader compatibility with media players