I cleaned up my post/instructions, thanks to digitalb0y for helping.
To install flirc on Windows 8 Consumer Preview (build 8250)
1. Move mouse to the left bottom corner and right click to bring up the administrative menu.
2. Click "Command Prompt (Admin)".
3. Type "BCDEDIT -SET LOADOPTIONS DDISABLE_INTEGRITY_CHECKS" and press enter.
4. Type "Bcdedit.exe -set TESTSIGNING ON" and press enter.
5. Reboot the computer.
6. Download and install Visual Studio 11 Professional Beta from microsoft.com. This takes about 50 minutes.
7. Move contents from c:\program files (x86)\flirc\driver to c:\test\
8. Move mouse to the bottom left corner of your desktop and open your metro start screen.
9. Open the "Developer Command Prompt" (type "developer" if you can't find it).
10. Type "inf2cat /driver:c:\test\ /os:8_x64" and press enter.
11. Move mouse to the left bottom corner and right click to bring up the administrative menu.
12. Click "Device Manager"
13. Find your flirc device > right click > update driver, choose the directory c:\test\ and ok.
14. The driver should be installed. Now you can run flirc.exe and program your buttons.
15. Open a command prompt (admin) and run "Bcdedit.exe -set TESTSIGNING OFF".
Basically, I believe this is a two step process. One is to allow signing of drivers in test mode. Two is to create a driver catalog file that Windows 8 needs. Then you can install the driver.