Currently it is not possible for the JIRA issue collector to create issues with 'Anonymous' reporter.

To reproduce:

• Set JIRA to allow Group (Anyone) to create issues within your project
• Set the Field configuration, setting the Reporter field to be optional
• Create a new Issue Collector
• Notice the red asterick( * ) that still indicates the Issue Reporter field being required
• Leaving the field blank and trying to proceed with the creation results in error:

  Please enter default reporter create issues in project.

Note: users can still anonymously create issues via Issue Collector, but the result is that the Reporter is still to a defined default user.