Redmine

This feature is already available in your Redmine version. Please see the /workflows/permissions section from the Administration page where you can set the standard and custom fields optional/read-only/mandatory for each status by role and tracker.

Thanks for the feedback. I wasn't aware of this functionality..

However, I've set the Workflow field permissions for the relevant role and tracker, and the system is still allowing me to change the status to one where the Custom Field is required,without it actually being required.

So - I'm a role of developer
It's a tracker of Story
For the role of developer and status '4-Ready for Test' the custom field 'Peer Reviewer' is 'required'

However, if I create a new 'Story' issue and save it as New, then update it an change it to '4-Ready for Test' the item can be saved without selecting anything in the 'Peer Reviewer' dropdown list. I would also have expected a red asterisk to be displayed by the 'Peer Reviewer' dropdown box but I don't see that either.

The options I actually see in the field permissions are

(a blank)
Read-only
Required

I'm assuming 'Required' means the field content is mandatory.

So, unless I'm missing a trick here, this functionality doesn't seem to be working. Can anyone confirm this?

The user that you used for these tests is Administrator? If yes, this is the trick, the workflow is not applicable for Administrators (from my experience with Redmine). Please try with a non administrator user.

Aha! I was aware of that potential issue, but I asked a non-admin to test it. Unfortunately they didn't test exactly what was needed.
On your advice I re-tested as a non-admin myself and it worked exactly as I would expect.

Thanks very much for your swift responses on this, it's very much appreciated!