Some of this could have been answered by reading Necron33's post, -
-
To mess with the drop rates for any item, you will have to manipulate the cq_dropitemrule. Playing with this table can also get rid of the magic boxes and cloth drops.
The problem you have in which nothing happens when you click the item occurs when the item action parameter in cq_itemtype either doesn't match up or leads to no ID in the cq_action. So, find the item ID of your ep cards, search for them in cq_itemtype, scroll over to that item's "id_action" column, and then take that number and search for it in cq_action.
If it
can't be found, you'll have to either find it, or write a new script for the item to give ep.
If it
can found, make sure that it's doing what you want it to do.