What system are you running? I'd recommend removing the demo version from its installed location, run BFD2, scan for new data and trash and rebuild the database.
You should have been asked to authorize BFD2 via the FX License Manager on launch of the app/plug-in, and after successful auth'ing BFD2 will automatically scan for data and then load the start up box asking how you play or program and if you have any BFD1 kits, etc...
If you updated to BFD 126.96.36.199 before installing the rest of the discs then I guess the combo's data patch hasn't been applied correctly.
Your best bet is to get in touch with the FX crew and explain in detail what you've done - including all details regarding your system setup/config. Or you may wish to remove any installed plugins and data and start over following the manual for details... then grab the data patches and latest version to install after.
Note: Mod's please move this into the "BFD2 thread"