You could create a region covering the desired area, and set a visibility emitter to emit black mask at that region. But if it has boundary, it should not be able to be seen anyway.
What doesn't work? You don't gain the unit, it doesn't appear in the store, or the unit isn't yours?
Make sure the store has the unit under Techtree - Units Sold.
People love some of the maps they make, and dislike others. If he hasn't updated it in a while, he has most likely moved on. I think as long as your brother writes down that the original map was made by <person>, and is now edited by <your brother>, it should be okay. However, if the creater...
1) I don't think so. However, you can make a variable and increase it by one every second to keep track of how long something has happened.
2) It issues a Follow order.
3) I have not.
I don't think giving them an inventory will work, considering the ability is called Unit Inventory. You could try making the building a unit who can't move around, but I don't think buildings can carry items like Heroes, unless you are buying or selling them.
I don't have World Editor open, but you could try something like this.
When a unit dies, create a circle of power for Owner of Triggering Unit at the position of the dying unit, and move a small region to the same position.
Then if a unit enters that region, and owner of entering unit is not...
It worked when I just did it. It may not have edited properly if you didn't have Use Custom Gameplay Constants checked.
If you changed the "Stats - Level Skip Requirement" in the Object Editor to something other than one, it will not be effected by the gameplay constant.
EDIT: Unless you mean...
Okay I did it and it worked. Here are my triggers (I used Banish to capture, and Chain Lightning to resummon)
Capture
Events
Unit - A unit Begins casting an ability
Conditions
(Ability being cast) Equal to Banish
Actions
Set TempTarget = (Target unit of ability being cast)
Set...
What if you applied a buff on the target of the ability for .1 seconds and used this:
Trigger
Events
Unit - A unit Dies
Conditions
((Triggering unit) has buff <Buff>) Equal to True
Actions
Player - Set (Owner of (Casting unit)) Current gold to (((Owner of (Casting unit)) Current gold)...