There are two particular errors the first is attempting to set a bp global for the plugin slug - the warning you report, it's actually not being used and effects things not although ought to be and will be removed, the other warning is of undefined variable , not really an issue, nice to clear those up but they don't cause failures.
However it's only an issue overall if you have error reporting on and on a production site you shouldn't have! On a test site agreed annoying but turn it off while testing the plugin.
The whole plugin is due for an overhaul on all the codebase, but that is a task and I have no time right now, and as the plugin does function and work that has to wait.
Lastly sorry for the slow response, we used to have our plugins on BP in groups with their own forums and where we mainly kept an eye on things.