You are correct that if you use my initial suggestion, it would not persist across versions. As such it was not good advice - just an attempt to provide an immediate solution to a problem nobody had ever raised before.
In the wake of that realization, the plugin has supported Google Analytics tracking since version 2.1, albeit in a more limited mode than you're suggesting. When enabled (it's exposed on the settings page in the download link options), it sends to GA a category of "Download" and an action of the URL of the downloaded file.
I use GA on an extremely limited basis and as such I'm relying on examples I could find online to implement this. I welcome your feedback as to whether or not it functions as intended and what the rationale might be behind extending the data further to include specific customization per URL or values for the optional elements. I would consider adding them (fixing-if broke/improving/extending this function) if I had a good tester and a better understanding of the purpose of each string and how it would normally be used by very GA literate people such as yourself.
Hope this helps.