I made a new enemy of the Leever type and gave it a rock projectile but it doesn't shoot the rock like it's supposed to. I haven't tried any other weapons with it yet. I'm not sure if this is cause Leevers have never actually had projectiles in a game yet but it seems like if this were intentional, it'd defeat the purpose the enemy editor.
Essentially I want to have a deku scrubs...they dig underneath the ground like a leever but also shoot rocks.
Actually, the Leever Enemy Type was never given any attributes for using projectile weapons... However, they may or may not add something like that for Leever Class after _L_ starts working on Enemy Editor 2.0, after post 2.50.
what you could do is make some water combos that look like the deku scrub's little hideout, make them zora type enemies and block link from walking on the combo so he doesn't drown or swim in it, depending on how you have your quest set up. that method would require your deku scrubs to shoot fireballs, as rocks don't go through unwalkable combos. if you're not having link drown in walkable water and you aren't using flippers, you could always make the water walkable and not block link from walking on it, AND use rocks as a weapon instead of fireballs. otherwise, you'll have to wait for your dream to come true unless you use some sort of script.