GASShooter Server Wait for Client Target Data

I’m trying to use “Server Wait for Client Target Data” and" Wait Target Data with Reusable Actor" for my GA that spawns a Projectile, like GASShooter does it.

But my Server does not receive that “Valid Data” execution pin of “Server Wait for Client Target Data” even though the client configure and send the TargetData with “Wait Target Data with Reusable Actor”.

    void UGSAT_ServerWaitForClientTargetData::Activate()
    {
    ...
        AbilitySystemComponent->AbilityTargetDataSetDelegate(SpecHandle, ActivationPredictionKey).AddUObject(this, &UGSAT_ServerWaitForClientTargetData::OnTargetDataReplicatedCallback);
    }

This get’s called from the server, but how does the ASC (UAbilitySystemComponent) knows what TargetData delegate to get from the SpecHandle and the ActivationPredictionKey?

I don’t quit understand the ASC->AbilityTargetDataSetDelegate() process.

Edit: Okay I found the counter part from ASC->AbilityTargetDataSetDelegate() (Server).

WaitTargetDataUsingActor (Client) does call
AbilitySystemComponent->CallServerSetReplicatedTargetData()

When trying to Debug CallServerSetReplicatedTargetData, it kicks me of right after the first if (it’s also weird that the breakpoint inside that else has an exclamation mark). I did started the project with “DebugGame Editor”.

Why can’t I debug this?

I had a latent function “Timer by Event” that seems to messed up Server Wait for Client Target Data. Without it, it works.