Every time i want to activate engineering team for myself i have to hit escape to cancel my target so i will not put engineering team on the target of my target because of assist.
Assist should not work on enemies, if i want to heal an ally i target him directly.
STOs targeting system is not THAT hard to understand ^^
first of all: you target a friend, you will use "backup skills" on him.
second: you target an enemy, the backup skill will be cast on you. UNLESS: the enemy has another friend in it's aim (eg, not you but a chummer), then you will switch to the friendly target and use your skill on it.
when you continue shooting after that, the target will automatically switch to the enemy target of your friendly target.