what DHK wrote is kinda right, but with a couple mess-ups, ( can be improved, and i dont want to even know what happened to that Custom Script line )
here we go - sped up, fixed, and written with the correct names
Events
Generic Unit Event - A Unit Starts the Effect of an Ability
Conditions
Ability Comparison - Ability Being Cast equal to Command Troops
Actions
Set Variable - Set Loc[0] = Position of Triggering Unit
Set Variable - Set Loc[1] = Target Point of Ability Being Cast
Custom Script - set bj_wantDestroyGroup = true
Unit Group - Pick Every Unit In Group and do Actions = Pick Every Unit in ( Units Within 1000 of Loc[0] ) and do Unit - Issue Order Targeting a Point - Order Picked Unit to move to Loc[1]
Custom Script - call RemoveLocation( Loc[0] )
Custom Script - call RemoveLocation( Loc[1] )
PS. requires an Array variable ( size 1, type Point )
Teh_Ephy - Begins Casting still works, it just suxorz ( oh, and i dont think DHK knows JASS )
TheMoneyLover - Custom Script is the 3rd action from the top of the list ( no category ), and is right under Comment. Also, the reason the script was not working was defenitely NOT the custom script line, as pretty much the only way that a GUI user will ever use JASS is to clean up leaks.