Welcome to LinuxMCE. The best advice that we can give, is to be patient, and if needed, talk to community members on the #linuxmce channel on irc.freenode.org.
To answer your questions:
(1) not that I know of, but if you're comfortable writing code in either C++, Ruby, or Shell scripting, a device template and resulting DCE device can be made that LinuxMCE can easily control.
(2) Again, not that I know of, we are always looking for solutions in this department, but nothing has been made widely available on any platform, save for Windows.
(3) I did write a DCE device for the Hulu Desktop player, but Hulu Labs has since discontinued it (as of 2012), and it will no longer work on current systems, so we have removed it from builds. We are looking for creative solutions for Netflix, as well.
(4) The Fiire remote was a custom remote designed by Gyration for Fiire Inc., These remotes haven't been made since 2010, and the support code for them was disrupting a wide variety of other devices in the system, so the code was removed.
-Thom