It's great that I can right-click on the project in the project workspace and be offered the opportunity to open the map file. However, different mapfiles are created by BL51 (<project>.m51) and LX51 (<project>.MAP) and the menu does not always offer the correct one. The logic seems to be that if <project>.MAP exists then that is the one that is offered. This can be a little confusing if, like me, you want to try out both linkers. The solution seems to be to rename or delete <project>.MAP if you are not using LX51.
My version doesn't even have this feature - must be time for an update! As a workaround, can you create separate Targets - one for BL51, and one for LX51 - and have separate listing folders for each?