JIRA BTF and JIM 6.3.0
Go to External System Import screen in JIRA
Choose to import data from FogBugz On Demand
Proceed with the steps to complete the import process
All the data is imported in JIRA and new fields are created in the target project if necessary
All the data is created, but is also created a Computer custom field associated with the project, even if there is no Computer field being used in Fogbugz before
If the field was wrongly created and you do not use or need a Computer field, you can just delete the field from the Custom field section in JIRA.