I have now, after a steep learning curve built a custom report based on the kind help I have has so far.
But I have an issue, that I don't know how to effectively resolve.
The report works online fine now with the desired output.
I built the report using the Example 101 - starting with 'Empty Report' and adding my SQL & columns as required.
But when I select an 'action' such as 'print' 'print to pdf' etc, there is a brief pause a refresh and nothing ..
Nothing is appearing in the php logs.
I have debug on. Nothing is showing in the CiviCRM log output.
There are no browser console JS errors.
All other reports perform as expected.
I'm working through CiviCRM debugging, any pointers here please - I'm so close but so far! (CiviCRM 4.7 - WordPress)