Fortress is a display addon for LDB data feeds. It shows each plugin as a block, which is freely movable and can stick to other blocks. Blocks can be unstuck by holding the ctrl-key while dragging them.
Use /fortress or /ft to open the configuration (also accessible via Main Menu -> Interface -> Addons -> Fortress).
The configuration has two parts: The master settings and the individual plugin settings. At first each option is controlled by the master settings and therefore it has the same effect for each plugin. Once you change something individually for one plugin, this setting is no longer controlled by the master mode (for this plugin).
You can select the mode for each option at the "Select master" tab in each plugin's config screen.
To report a bug, please open a ticket here.