Been listening to this all week along with a deeper variation of the core piano theme - the strings need editing but you can hear where they're going. I love the initial C# where the top string comes in - it delivers a subtle spookiness which is appropriate I think for this theme!
Don't forget to check out membership - free members get to download the writer's playlist which contains Frustration - but you'll need to be an annual member ($15) to get this track when it is published