I read the forums, disabled the Windows User Account Control, checked with "Steam Skyrim properties" the local files, deleted for trial the files skyrim_interface.bsa and ControlMap_Custom.txt , nothing worked. So I uninstalled Skyrim and Steam from my Win 7 PC and reinstalled it, did NO key mapping, but the missing control keys still do not work!!!
I do not know the error reason, but two points in my installation may be peculiar:
1) I have installed Skyrim to the d:\program files directory and NOT on c:\program files
2) I use 2 monitors with my GForce GTX660. Skyrim displays at the secondary monitor.
BTW how and with what control key I do pick up things into my inventory??