Sorry for the noise, this is more a thank-you thread than anything.
I managed to fix my little problem, without even asking, thanks to the search function on these forums. I had to cut bits and pieces from several threads ,but I did it (I'll post a recapitulative how-to thread for those who might come after me).
Despite many obstacles (loss of my original remote, harmony techs crippling their remote with stupid software, and sharp issuing a bazillion projector with different codes for each one of them) I managed to find the hidden advanced menus, process the codes to make them usable and enter them in the interface and finally my remote is working has it should.
I have been through remote-hell and this is really not a nice place to be, but thanks to the knowladgeable and helpful people here, this board was like an oasis in the middle of bat-country for me.