Since Arma 1.78 scripts that add event handlers to AI are returning Unknown enum value errors. An example from the logs is shown below:
_ai1 addMPEventHandler ["killed", {[(_this se>
21:50:13 Error position: <addMPEventHandler ["killed", {[(_this se>
21:50:13 Error Foreign error: Unknown enum value: "killed"
The original line of code that caused the error was:
_ai1 addMPEventHandler ["killed", {[(_this select 0), (_this select 1)] call compile preprocessfilelinenumbers blck_EH_AIKilled;}];
Thus far I have seen this error with "killed", "MPKilled", "reloaded" and "hit" event handlers.