Control ability problems

[Keiga]

I am trying to make an ability that takes control of units in an area for a certain amount of seconds and for each one controlled the caster loses 10% of his max life. Here are my triggers.

Tidal Control
    Events
        Unit - A unit Begins casting an ability
    Conditions
        (Ability being cast) Equal to Tidal Control 
    Actions
        Set Targetedpoint = (Target point of ability being cast)
        Unit Group - Pick every unit in (Units within 800.00 of Targetedpoint matching ((((Matching unit) belongs to an enemy of (Owner of (Casting unit))) Equal to True) and ((((Matching unit) is A Hero) Equal to False) and (((Matching unit) is A structure) Equal to False)))) and do (Actions)
            Loop - Actions
                Unit - Change ownership of (Picked unit) to (Owner of (Casting unit)) and Change color
                Set Unit = (Picked unit)
                Set PLAYER = (Owner of Unit)
                Wait 1.00 seconds
                Unit - Change ownership of Unit to PLAYER and Change color

For this one, I am able to take control, but it doesn't change back to the owner after the wait time.

Wid
    Events
        Unit - A unit Changes owner
    Conditions
        ((Ownership-changed unit) belongs to an enemy of (Owner of Legendary Tidal Dragon 0000 <gen>)) Equal to True
    Actions
        Unit - Set life of Legendary Tidal Dragon 0000 <gen> to ((Max life of Legendary Tidal Dragon 0000 <gen>) - ((Max life of Legendary Tidal Dragon 0000 <gen>) / 10.00))
        Unit - Set mana of Legendary Tidal Dragon 0000 <gen> to ((Max mana of Legendary Tidal Dragon 0000 <gen>) - ((Max mana of Legendary Tidal Dragon 0000 <gen>) / 10.00))

For this one nothing happens when the unit changes.

Please what are my mistakes? thanks

 

[AceHart]

No idea, really.

But
"Unit - Change ownership of (Picked unit)"
followed by
"Set PLAYER = (Owner of Unit)"
makes that "Player" is now the new owner.

 

[Heptameron]

For this one, I am able to take control, but it doesn't change back to the owner after the wait time.

That's because waits don't work in Pick actions.

For this one nothing happens when the unit changes.

All that trigger does is, whenever a unit owned by an enemy of whoever owns the dragon, the dragon jumps to 90% health and mana. I doubt that's what you want.