I don't have an answer, but request that someone provide specific information for disassembling this particular remote, since I have the same issue as elmarimed (but for different keys).
I'm afraid to pry apart the remote if there is a chance that there are other hidden screws (under the sliding panel on the bottom front, for example). I tried to remove that panel to see if there were more screws, but couldn't figure out how to do it.
Thanks in advance for any help.