This is specific to Chrome Version 45.0.2454.101 m
In general, Identity Safe is working fine; but on some sites it keeps me from logging into the site. Typically, it fills in my user name and password correctly; but then the actual "login button" on the site is inactive. Identity Safe doesn't complete the login for me, either.
If I close the vault, I can log in by filling in the fields myself.
It seems to afflict only some sites. I haven't noticed any pattern.