I noticed that items were disapearing when bug was happening, not sure if its related to resolution or not, but possibly - I indeed could click on party members outside of the inventory menu and try to select other comands and such.
And yes, probably why I never understood melee were autorepeating is because I was spamming everything until things were dead! Making it nearly impossible for me to notice... maybe some 'repeating action' icon next to cooldown line or something similar in future (if there will be continued work) could help to show it.
(Also laughted on possibility of wearing only one boot - sounds uncomfortable)