Finally saw this. Technically impressive (I especially liked the unstable-looking Praxis in the Klingon sky), but the story ran out of momentum once they reached Kronos.
I'm also disappointed that what began as a "real" Phase II (as in, the unmade 1970's sequel series) episode was turned into ENT-TOS-TNG Klingon continuity porn. I wanted to see what was originally
planned for the Klingons before their TMP/TNG re-imaginings. I like my fanfic to ask "what if...?" rather than to connect the dots.