Problem with trial of ascendancy 4th final boss

Hi, my name is Grzegorz, in game "Vakrii"and I have big issues with the final boss in the 4th trial of Ascendancy. The game freezes, shows me an error, and goes back to Windows. I have 12,000 honor points to beat the boss, and every time I log in, it starts again with fewer honor points and the same error. I play as an Infernalist in demon form, and the error message mentions a demon form error.
This error show when bos is 30%hp

Error window show this
"Metadata/Effects/Spells/maneuver_mechanics/Afterlmage/DemonAfterl mage": Error: Metadata/Effects/Spells/maneuver_mechanics/Afterlmage/DemonAfterl mage.ot is non-virtual and does not have a physical file