Small Update: Release 2.5.1 is out now, fixing that issue:
I can confirm your results from step 1 to step 5. This is indeed a bug that needs fixing; I have added it as http://jira.xwiki.org/browse/MOCCACAL-91
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1. Created new XWiki 7.4 instance - distribution wizard doesn't start for some reason so I installed the default pages using xwiki-enterprise-ui-mainwiki-all-7.4.xar. 2. Installed MoccaCalendar extension and verified that version is 2.5 (full calendar macro is version 2.0.2) 3. Logged in as Admin and created a new calendar (first to verify behaviour without your suggested mods to JSON Service). 4. In the new calendar created an event - event is displayed as expected. 5. In the new calendar, tried to create another event with the same title - event form displays 'An event with this name already exists.' under the title field. 6. In the new calendar, tried to create another event with no title - event form displays 'Title field is required'. 7. Deleted event created in step 4. 8. In class editor MoccaCalendarEvent class added new field 'Test' of type String. 9. Navigated to /xwiki/bin/view/MoccaCalendar/JSONService -> Edit -> Source and replaced $itemdoc.getPlainTitle() with $itemdoc.getValue('Test') in two places as you suggested. 10. Returned to new calendar created in Step 3. 11. Invoked form to create an event - event form is displayed with new Test field (blank). But the Title field is populated with a random string and the Calendar drop down field where you can select which calendar the event belongs to is missing from the form. 12. Entered a value in the Test field and saved the event - the form disappears but the event is not displayed on the new calendar. 13. Navigated to Calendar Overview and observed that new event is displayed there with the content of the Test field instead of the Title. Here the event is displayed on the Month view the way I want it.
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