how do i get firefox for u3 vertion 2.0.0.4 to vertion 2.0.0.11

The Firefox for U3 package hosted on U3's site is an unofficial, unsupported package. It uses some very old code from Firefox Portable with known bugs (leaves things behind on PCs, doesn't support all features portably, etc) and is not supported by Mozilla or PortableApps.com. So, if you wish to update it, you're pretty much on your own, unfortunately.

The other option is to use the real Mozilla Firefox, Portable Edition from this website that works on any flash drive. You can copy your profile from an old copy of Firefox for U3. The files are located here:

?:\System\Apps\3C9F7B3F-D55C-42cd-8537-B878518B73AF\Data\profile

Install Mozilla Firefox, Portable Edition and run it once to let it setup its folders. Then clear out the contents of its profile and copy in the one from your old U3 install above. The profile is usually located here:

?:\PortableApps\FirefoxPortable\Data\profile