The user should be able to choose from plugins and maps in pre-defined folders, and upload custom maps. Depending on the relative difficulty, maps might be validated on upload or BZFS will check them on startup. (Although it would be interesting to do the same for plugin files, there likely wouldn't be any nice way of keeping it secure.)
There should also be very few external tools used in this project, so that it can be deployed as widely as possible. It could be written in PHP or another common scripting language, but that would require whatever language chosen to be present on the host machine. Since BZFlag itself is written in C++, using that language would eliminate the dependency. It would also allow the admin interface to be implemented as a plug-in, using the in-port HTTP feature of the BZFS API, which would likely make it more convenient to deploy. However, in order to ease development, I may use a scripting language to create a working prototype and use that as a blueprint to rewrite it in the lower-level language.
BugQ will be carrying out tests on the config files generated by the tool as well as hosting a test server for others to try and give comments on.