Same here.
“Error: Your current WordPress Beta Tester plugin configuration will downgrade your install to a previous version – Please reconfigure it”
I have configured “Bleeding edge nightlies”
I already have 3.7-alpha and after upgrade I get 3.7-alpha (latest build).
If I “reconfigure” I get 3.5.3, so no way to get 3.6-RC2-xxx.
Conclusion: The error message is saying the opposite of what will actually happen. Because, if I reconfigure it, it will downgrade.
I have a issue like this as well I thought it may have to do something about multisite since I cant access the settings from the multisite options and need to go to one of the multisites, then as soon as I save the settings it bugs me that my setting would downgrade, funny fact I WANT TO! but it keeps downloading the latest beeding edge nightlys.
Even After I completely deleted the plugin, what btw was only possible manually since there was no delete button in the admin after deactivate like on other plugins, the update screen still downloads the lastest…
It is a feature/bug 😉
The plugin isn’t intelligent enough to cope with trunk being a different version from what api.ww.wp.xz.cn says it is.
So before 3.6 was released the API said trunk was 3.6 but the code said it was 3.7
So as far as the plugin was concerned upgrading would have downgraded you to 3.6
In the long term we want to be able to have better support for tracking particular releases in the plugin but we don’t have that yet.