I've just bought a Sandisk Cruzer Micro (4GB) and installed a few new apps on it. One of these was Firefox for U3. I've used Portable Firefox for some time (with PStart) and would be totally lost without it now - great app.
On the U3 drive it appears to have overwritten the default (Sandisk) Firefox U3 install which means the "Sandisk U3 Website" link in Launcher won't work nor will "Support on the Web" link within Launcher.
Additionally when I try to upgrade CruzerSync I get the message "Firefox for U3 cannot be started. You may wish to re-install to fix the issue. (ERROR:The program could not be found: H:\System\Apps\EC30627F-0195-44d4-1B09F3C02C50\Exec\firefox\firefox.exe)"
Firefox for U3 runs fine just from the Programs section of Launcher. I have to say I think this is more an issue with the Sandisk embedded software getting confused, but any help would be appreciated.
I don't know anything about the Sandisk embedding myself. The Launchpad links should actually instantiate the built-in U3 browser which is actually an instantiation of Internet Explorer... not FF for U3. I'd say drop Sandisk a support request.
Sometimes, the impossible can become possible, if you're awesome!