You need to modify the Flash template. This is at
Windows: C:\Program Files\Adobe\Adobe Photoshop Lightroom 4.x\Shared\webengines\default_flash.lrwebengine
Mac: Applications\Adobe\Adobe Photoshop Lightroom [version]\Shared\webengines\default_flash.lrwebengine
Copy that lrwebengine to
Windows: C:\Users[user]\AppData\Roaming\Adobe\LightroomWeb Galleries
Mac: [user]\Library\Application Support\Adobe\LightroomWeb Galleries
Open the file galleryInfo.lrweb in a text editor. Notepad is fine on Windows, or . . .
AutoSync mode in Library means that metadata changes apply to all the selected images, and is normally enabled by clicking a switch in the right panel (F8). But what if that switch isn’t visible?
It took me a while to figure . . .
It’s because the Flash gallery’s SWF (the Flash file) isn’t colour managed.
Flash does now support colour management. But the SWF would have to be ActionScript3 (the version in Lightroom is AS2)
You also have to consider what the person viewing your . . .