Having the exact problem... except when I tried --force-depends, I didn't get an error like you did. I think. HUGE list of comments resulted with that one.
I see my checksums matching, just getting one line from the luci "install", and no working luci after.
Ah, the joys of trying snapshots out on the family router! 
At least my life isn't in imminent danger, I have the house running off a travel router till I get this fixed... 