I will try to suggest a practical idea (maybe, its a 30sec brain function

) that you dont need change resources. (Also random values putted at example)
At cmbScript_click (the combobox that list the scripts) you can put some code to check the scripts starting lines and if it meets something like:
<arguments/>
argument0 = "Object","-1"
argument1 = "X","100"
argument2 = "Y","100"
argument3 = "Direction","90"
argument4 = "Speed","4"
argument5 = "Gravity","0"
</arguments>
Put at labels of the "Execute Script" window, that write argument0,argument1,... ,the 1st "" of its line, like "Object","X","Y","Direction",...
Then check if the TextBox that handle the user input of its one argument values, for being "", and if it is, change the value to the 2nd "" of the argument line, like "-1","100","100",...
Also put the cmbScripts_click called at each "Execute Script" window load, so even if someone doubleclick the DnD icon for edit or something, do a recheck.
I know that it isnt the best idea, but its a fast suggestion that use the "execute script" window resources. i dont know if this is a help.
Also sorry for my english and for my programming logic
