Permissions: restrict transition [via Workflow Button] access based on User Role

I am nog sure what you wish:
- change all workflow buttons back to radiobuttons/checkboxes and normal action buttons, per user role? At the moment, this is not possible, but you can create your hook_FORM_ID_Alter() function.
- limit the number of buttons, based upon the access set to the user. (This would be a bug: only buttons for allowed transitions should be displayed)

This works as designed:
- Maintain state transitions in admin/config/workflow/workflow/WORKFLOW_TYPE/transition_roles
- Under Permissions page, make sure the role required has proper permission to work with workflow.
- test with a user with configured role.
- Make sure you are not using User 1, since that used bypasses all access rules.

You can test by toggling the field 'How to show the available states' between Buttons/Select in /admin/config/workflow/workflow/WORKFLOW_TYPE.
The resulting permitted states should be the same.

Please check workflow.api.php or the Event subdirectory for code examples.

Unless your problem is with the settings in the following page: /admin/config/workflow/workflow/WORKFLOW_TYPE/access .
If so, please reopen with some more details.