I have successfully published the UPK LMS content and hung it on our Training environment.
I have no problem using Internet Explorer (whatever version) to See, Try and Do but when using Firefox 5.0 - the menu paths and navigational controls disappear then freeze.
While Firefox 5 is not officially supported, it may be worth downloading UPK 11 (the recent successor to UPK 3.6.1), which added support for Firefox 4 to see if you have better results. UPK 11 Tech Specs: http://www.oracle.com/us/products/applications/upk/upk-tech-specs-434459.pdf
If you would like to enter an enhancement request, please submit a ticket in My Oracle Support (http://support.oracle.com/).