Thanks for the feedback, don't worry about dominating the thread
So far most of the enhancements to this plugin have been tailored for my personal workflow, input from other people to make it more generally useful is greatly appreciated.
The series identifier idea is a good one. The 4050 is not actually part of the volume id, it is an identifier for the "Volume" (series) resource type (similarly the resource type for an issue is 4000).
I will take a look at how I can integrate this into the plugin and let you know when I have it working