Q: How to synchronise JIRA work log with MS Project task usage data on user by user basis?
A: Please go to JIRA -> Project Settings, select the "Time tracking" tab, tick "Time Spent", select "Daily actual work" and then tick "For each assignment". This will populate the time scale entries for your tasks with the data from JIRA work log on user by user and day by day basis.
Please note that the option is disabled if the Assignee is mapped to MS Project Resource on the first tab page. You need to map assignee to a text field or avoid mapping it at all to enable the "For each assignment" option. The reason for the limitation is that MS Project allows assigning multiple resources to the same task while JIRA does not. "For each assignment" option implies associating multiple resources with the same task. At the same time, there is no way for the user to tell Ceptah Bridge which particular resource to use as assignee. For instance, it would not make sense to use the first resource from the Resource Names list as the order is simply alphabetical.