Odin, you can check out my
arty.
Take apart the shellmon.sqf and add your arguments line at the very bottom.
Use _pos as the last position of the shell.
The arty.sqf uses a spawned projectile, so your going (sand have my permission) to dissect and reassemble it to your needs.
All you need is the basic arguments, which I don't have at the moment (not by my arma computer),
and execvm shellmon.sqf from your script.
The effects line is commented because I need help with the Switch:case commands,
but I can put in a
single custom warhead into my arty script.
If you would like, I'll try and see if I can get that for you.
If not, I'll see if I can get a custom version for you.
And remember: it is a work in progress.
Luke