Using Garmin Legend HCx with ExpertGPS

Hi

I'm trying to set up my program ExpertGPS for use with my GPS. What I want to do is to overlay a scanned map of somewhere in Ireland with GPS tracks. Have tried to set up ExpertGPS for this but each time I scan a map, calibrate it & then download the track, I find that the track is not overlaying properly. Have I missed a setting somewhere in the program. I need to be able to do this as I need to produce overlaid maps for my local walking/rambling club. There is no user's guide to be found & the expertgps wensite is very difficult to navigate. What I have already done is to go to preferences and set Irish Grid, then set Garmin receiver, not sure about anything else. Any help would be very much appreciated ASAP. Many thanks.