translation and a few more details:
boss1:
- Combat Banka is always the hardmode mob (therefore massive auto-attack hits on easy/normal)
- Phase change every
10% - if you instagib the boss for
more than 20% at once(either instantly or "faster than he can switch back into his Banka") though, the switch in/out of Combat Banka might get stuck (=> Combat Banka with boss in/on it does not do anymore what is needed to get him OUT of the Banka in the first place => fight stuck) - concerns mostly easy and normal due to HP/Def values.
- boss2:
unlike the first add, the second adds can die prematurely (instead of "going away") - this CAN lead to a stuck fight (no transitition to third phase) - simply do not cut them down to 0% HP totally for now and you should be fine. (It is not part of the mechanics that those actually DIE, something else happens - but it seems a "immune at 0% HP until stuff/script happens" is missing there, like the first mob has.)
-boss3:
- its Barrier didnt reopen (once) after aggroresets/wipe etc , reason unknown, might be related to aggro-resets (vanish etc)
- boss4:
- Hi I'm boss4 and I'm on strike and will only do my tactics if I feel like it - reason unknown (this also did NOT happen before live...

) -observed once or twice on live by now , reasons unknown.
boss5:
- has a phase change/transition at 50% - if you attempt to KILL the remaining 50% off of him during that few seconds of transition (and succeed with that!) , the final mob was once observed being stuck at 0% instead of dying. Most likely easy/normal only (or Champion/Mage :p) issue.
All of the above has already been reported to Runewaker.