Why is Kivy Launcher giving "your device isn't compatible" with Nook HD+?

When I bought my Nook HD+ a week after Google Play was enabled for it, one of the first apps I installed was the Kivy Launcher. It worked great for a few times, then stopped working mysteriously - wouldn't even generate a log file. I finally decided to uninstall it and reinstall again. Now when I go back to the Play Store, it shows a message under the app icon: > Your device isn't compatible with this version. I have no idea why it wouldn't be compatible, since it worked the first time I tried it. Is it possible that B&N black-listed it? What other conditions would generate this message?