Don't do it for player do it for a unit.

Oh!
Btw, the variable "-Player" was an integer set to "1".

But still, with "Unit" it doesn't work either. ;o

Ok, so you can use unit or ability in this case but you need to make sure it matches the Location in the cost for the ability.

Ah! It was still "Ability".
Now it does add charges, though it looks like my simple "-1" gives an infinite amount of charges O_O
My max count is 3, so it is set to 3, but whenever I cast the spell from there, it stays on 3.

What is your count start?

2.
And I've set it to use 1 charge per use.
Reminder: Max is 3.

I can't seem to replicate the problem you are having, it is probably something else in your triggers that is causing the give charges trigger to happen constantly.


BTW for debugging purposes using windowed mode with the trigger debugger is awesome. To do this go to Preferences->Test Document and then have run in window and use trigger debugger checked.

With the trigger debugger you can see when triggers run have many times their event has been hit, how many times they have failed their conditions. You can show all your trigger variables (in the variable window right click) and see the trigger queue.

http://www.mediafire.com/?bw9hnyz7340oby7

I have comments a bit everywhere where I need bug-fix... if ever you feel like it.

*Bump*
Please please, help fix!

Your pickup event is wrong, should be any unit and then have a condition for unit in unit group.

Nice, now it works perfectly.

Now, may I know why whenever a Seeker Missile is cast, the Pick-Ups are removed?! O.o

I don't get that at all, although you have it set so whenever a new pickup is placed on the map any other of the same type is removed. Also if your going to use an If else {if else {if else.... kind of setup you should use a switch and not an if.

I noticed that your location for pickup is not large enough (I think) and should be the size of a square (or almost the size of a square so it cannot get into other squares)

What do you mean? I do not want a pick-up to be picked by a player simply because it is in the same square. I want the players to move toward them.
And I've fixed my problem by excluding the count of all weapons with a condition since ammo unit (weapons) are considered as units.