Delay with spell

Hi, I modified a spell from and original (Carrion Swarm) and set the cooldown to 1 second. But after he casts the spell theres a moment of nothingness... he just stands there for 3 seconds.
Does it have to do with the model -Marine-
Would it work beter if i used shockwave in stead of carrion swarm?

maybe the casting time is really high?

cast backswing point in the object editor effects how long it takes units to cast as well as casting time. (unit editor)

Its either backswing point or casting time. Both can be found at the very top of the unit's list of fields.

Wat should i set the backswing to?

A lower amount. Any caster who uses a spell will sit there for a bit before doing anything, unless directly told to. It can be seen in games, like after an archmage makes water elementals, for example.