There are a number of bugs reported here. But it isn't sure if anyone at Garmin reads them. After all, it's a user-to-user-support forum.
I don't any formal way to report bugs. Maybe using email has a better chance of getting to the development team.
For betas you can use the email address listed with the beta announcement; often [email protected] or [email protected].
And/or use the Share Ideas page.