FL 11.1, both 32- and 64-bit version, the plugin database was slightly messed up. A few folders and files associated with FL native plugins that weren't in my database before were added. Eg bmp-files of Gross beat ...
FL 11.1 update all my VST plugins (synths & effects) are deselected from the list. I have to manually select them again. I remember that the last update did this aswell but never really bothered to mention it.
Offcourse I'm reselecting ...