Hi there is a test version of the plugin available on
http://kelsos.net/musicbeeremote/download/ and instructions on how to get the test version of the application.
Remember that this version of the remote/plugin is incompatible with the previous version, so the old plugin won't work with the new application and the new application will not work with the old plugin.
Google Play has added support for alpha and beta testing, though it needed me to either add a Google+ Community or Create a Google Group,
in order to get users for the testing. I chose the group and I created one, on the group welcome message there is a link to follow to opt-in for the testing. Afterwards the test version should be available to you through Google Play. The test version is 0.9.1.
Keep in mind that in the new plugin the settings panel should be under Tools/MusicBee Remote. There is also a known issue, if you change the port you have to restart MusicBee in order to activate the new settings, it will be resolved in the following days.
Also now the connection settings of the application are under Settings (either menu button on older devices or overflow menu - settings) on the Manage Connections entry.
I will create a more detailed help in the following day however in the meanwhile feel free to ask.