The plugin allows you to disable/enable plugins and/or activate a default theme for checking conflict between them only for your IP; other users won’t see any changes during the tests.
It is made for developers, techical support engineers, as well as for regular WordPress users. Sometimes, usually after updating your plugins, themes or WordPress installation, strange issues may appear and mess the things up. This plugin provides a really neat way to check the problem.
Developer explained what was going on when it was trying to install in another place. At first, I thought this was a shady plugin. I still think that the information should be transparent from the beginning before installation and later very well explained if it is trying to do something like to install itself in another directory as a MU plugin (which I didn't even know existed).
I raise my rating but still think all this should be explained well before so that once more users are not confused because of strange plugin behaviors if those are not very clearly advertised before.