Originally Posted By etabeta78
I would be more interested in understanding how nestopia will handle the xml inside the zip.

It's pretty straightforward. It searches for an XML file inside the ZIP (any name will do), reads it and then, guided by the XML, loads and assembles the raw binary files (also inside the ZIP) to be used for emulation. In other words, NES and UNIF files inside the container won't work. The only way to utilize them with the XML format would be through a database.