Detect attempt picking up item

How can I detect if some one is attempting to pick up a item even if all of their space is taken up.

Try using the event "unit is ordered targetting an item" or something like that (dunno if it exists)

Use the event: Unit - Generic Unit Event and set that to "A unit is issued an order targeting an object"

Keep in mind this triggers whenever your unit right clicks almost anything, units, doodads, items, etc... so with the right conditions in your triggers it should work fine.

probobly something to do with, a unit is issued an order targeting a object

with the order in question being smart/right click. Remember that moving an item inside your inventory fires this event too.