I've duplicated the sentry's force-shield ability and gave it to a marine. I wanted to change that ability so it cast forever til the death of the marine but do not understand how because its a persistent effect with 30 periods at .5 duration = 15 second spell..
How to make a ability constant without having the marine auto-cast?

Another problem is now that anytime i create a marine on the map, the blue hex model creates on him even if no force-shield is nearby. I've attached a picture to explain what i'm talking about. i will PM you the map if you would like to see for yourself.
I've looked in the actor-events and nothing is creating that model at birth..

Quote from Bolshevik09

I've duplicated the sentry's force-shield ability and gave it to a marine. I wanted to change that ability so it cast forever til the death of the marine but do not understand how because its a persistent effect with 30 periods at .5 duration = 15 second spell..
Tried to get him to auto-cast it as well but could not get him to.
-removed the cost, set the auto-cast range to 5, removed cool down, checked the flags

If you want it to last forever after casting it, I think you can just change the periods and duration to 0. It's been a while since I've looked at that, though. If you want it to show up as soon as the Marine is created, you can bypass the ability altogether and just put the Behavior on the Marines from the start. You don't even need to mess with auto-casting or anything. If I remember correctly, when the Force Field ability is used, it adds a Behavior to all units inside of it. Theoretically you can just put that Behavior around the Marines from the start, and have the shield model appear when the Behavior is on. You can also go as far as to make it add the protective Behavior to other units nearby through the initial Behavior and the Area/Persistent Effect.

Quote from Bolshevik09

Another problem is now that anytime i create a marine on the map, the blue hex model creates on him even if no force-shield is nearby. I've attached a picture to explain what i'm talking about. i will PM you the map if you would like to see for yourself

We'd probably have to see the map for this one. It should only show up if they have the behavior active on them.