0.9.2.6 and .7 are completely broken

I’ve got a MU subdirectory installation and W3TC activated on a single blog. 0.9.2.5 worked perfectly for me. However, since the upgrade, things are pretty weird (both with 0.9.2.6 and the 0.9.2.7 today). I get the W3TC dashboard, but no configuration options and the plugin is not even visible in the plugins list, so I can’t deactivate it 🙁

http://wordpress.org/extend/plugins/w3-total-cache/