I am 99% sure I found a bug, but can't isolate the repro easily and would have to post a big capx. If I get some time later or these days I'll start removing stuff one by one and then take it from there. But the jist of it is this:
To my understanding the disabled line (Spawn) should be equivalent to to the System.Create. However, if I disable the Create and enable the Spawn, the Set bullet angle of motion does not work on the created rocket.
It took me a while to come up with the workaround, please let me know if you have any idea why it wouldn't work with Spawn.
As I said, I cannot repro this on a clean capx.