I don't have a Roland 3 zone cymbal nor a mock up at the moment so this is from my memory.
Roland 3 zone cymbals use 2 consecutive stereo inputs. For this example say Aux1/Aux2.
1. Plug the Bow/Bell cable into Aux1
2. Plug the Bow/Edge cable into Aux2
3. For Aux1 Head set Type to 3way Roland
4. For Aux1 Rim set Type to Switch
5. For Aux2 Rim set Type to Switch
6. From
http://www.megadrum.info/content/miscellaneous-settings use 'Set All EdgeSw' option to auto-set Threshold on Aux1 Rim and Aux2 Rim. After completing this procedure you will have Threshold on Aux1 Rim and Aux2 Rim set between 1 and 50. You may still adjust these Threholds slightly so that when you press/release either the edge or the bell switch you get MIDI Aftertouch On/Off messages. You can use either MegaDrum Manager or MIDI-OX to monitor for MIDI Aftertouch messages.
7. At this step you should have zone separation for all 3 zones and you will need to configure all other parameters (don't change Gain setting otherwise you will need to start from step 6 again). Bow settings are in Aux1 Head, Edge settings - in Aux2 Rim, Bell settings - in Aux1 Rim.
When I find my Roland 3 way mock up (lost somewhere) I'll check this steps again.
These topics also will be of help I believe:
viewtopic.php?f=3&t=889viewtopic.php?f=3&t=376viewtopic.php?f=3&t=572