Problem with Workflow Edit Permissions

I've been using Drupal for a few months now, but have only recently tested the workflow module on one of my sites (for submitting creative writing). I started with workflow-ng, and loved the functionality, but prefer the simplicity of the linear workflow in the "workflow" module.

I've been building a workflow one step at a time (to get used to the module). Basically, I created a new content type "short story", and have assigned the workflow to this content type. I have also created two user groups, being "writer" and "content moderator" (more groups will be added once I get the first steps sorted out). Basically, the problem is that the workflow edit and view permissions are overruled by the generic group permissions, but also don't provide groups with a minimum permission.

I have had no problem creating a new short story as the writer (who is permitted to create, edit own, view revisions, and access the workflow tabs available - generic group permissions). However, these permissions permit the writer (who will naturally be the author) to edit the content even when the state changes from "draft" to "submitted to content moderator" - when the edit option has been unchecked in the workflow options.

Additionally, the content moderator is unable to edit or even view the content when the state has been changed to "submitted to content moderator". In the workflow, the content moderator is able to view and edit the short story, and the content moderator is permitted to access content, edit content and view revisions in the generic permissions options. The only way the content moderator is able to view this content is if the generic permission "administer nodes" is enabled, but this far exceeds the permissions that should be given to this group level.

I haven't added the actions module yet (although I can't see how this might influence this problem).

I'm guessing there is an obvious conflict that I've overlooked, but I cannot find it.

Thanks in advance for your help.