Hi,
Thanks for this very clear report.
I'm happy to tell you that the arrow down/up problem is fixed.
And the crash is fixed too.
This will be fixed in the next release. I don't now when, but soon. It will probably be available only on the web.
In the mean time if you want to, you can send me contact me using PM, so you will be in the mailing list for the Beta test of the next version.
By the way, the VST3 in the AU is because the AU is based on it. So do not throw it away, and to be clear you should never modify the content of a bundle, the idea was to bundle it so it is clear that it is a part of the AU.
Best
Adrien