Latest version throwing a null pointer when you try to configure the field (select the role). Existing fields working as expected and can be edited/modified. New fields can not be configured.
Issues in
JIRA v5.2.11 and JIRA v6.0.1 plugin version v1.7.1-JRA-5.2
The fix cam e from Jamie Echlin and can be found here, im a comment dated May 29th:
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