Hi,
I don't think it's related to your other problem. Here it looks like the SetProperty action is trying to reference a class or property that doesn't exists anymore.
did you remove a framework or an asset you had from the asset store since the last time it worked?
Are you using the latest version of PlayMaker. I recall some issues like that, and I was pretty sure it was sorted, else I'll escaladate this case internally.
Bye,
Jean