I've pushed a fix to the store for this, will need to wait for it to be approved, then it should be resolved.
cool ----
Keys and purchases look correct, just make sure they're enabled as it's all disabled in your screenshot. The background is green when enabled, red when disabled. Make it the opposite to that screenshot and the store is setup correct.
Can you try enabling "Only summon in combat using instant cast abilities" please? Make sure auto summon demon is enabled too.
You should disable burst mode and auto enable burst mode for PvE. It's more aimed at storing cooldowns for PvP bursting.
When stunned -> It doesn't block all casts as some things can be cast while stunned (unbound will, sacrificial pact etc). IsValid, IsAlive, and !IsMoving checks would have no baring on this at all.
Spamming abilities before the last one has ended is intended due to the spell queuing system which blizzard implemented to help cope with latency. That's intended.
When moving manual -> Why would it only use instant casts? It depends on your talent build, but KJC for example would enable channelling when moving.
I think you're confused as to what Grimoire of Sacrifice is.
If you have GoS then you want that buff to be active at all times, you wouldn't take that talent and have a pet alive too.