Do not know if I can help you.
My setup is that I am using iTach GC IR trans-receiver over LAN (IP over ethernet). This GC device is able to capture the IR codes from the physical remote in iTach GC format and then I use a converter tool to convert the IR codes from iTach GC to Pronto Hex format.
The converted Pronto Hex IR code is then coded in the remote.lua file based on an example provided by the developer for Custom IR remote.
I have heard of the Zaza Remote Micro USB dongle which you do mention and am keen to purchase one only for the Learning purpose.