2 things..
Do a search in google for "hyperfocal distance focusing" ... great for landscapes as you get the best depth of field for your chosen aperture. Its easy to do and doesnt require using the RF patch at all. All my work is shot using this method...If your shooting landscapes where you want EVERYTHING sharp, this is your best way to go!!!
Second, in my early xpan experience i found my photos were pretty hit-and-miss as well. The meter in the xpan is the only thing that is crap about the camera (IMO) ... it is tricked very easily and is made worse by the fact your shooting such a large frame (in pano mode anywayz). There are a few tricks you can use to overcome the cameras dodgy metering, one method i use with very good results is to meter off the back of my hand held arms length from the lense.. Its *similar* to a grey card and usually helps your exposure.. (unless in some instances you could be standing in a shadow and shooting a sunny scene)...
Generally the xpan overexposes... that is, when the meter says its right on the money, the image is generally overexposed. My advice would be go out and shoot a few test rolls, take notes of exposures, and shoot a half to one stop UNDER exposed according to the meter.
Best of luck
Ben