Hey hey! I can get you added, I take it your username is the same as on here, and you're in the XS Discord?
Sorry for any added trouble here! Just sharing my experiences, I haven't fired up 0.51 but my testing was done on 0.50 yesterday. Admittedly I've buttoned up this console for now as I was looking to get this done prior to some other things grabbing my attention (totally not the Switch 2, nope, not at all), but I'll answer what I can:
I was able to dump and flash the BIOS using the Python scripts. I was originally trying to dump just to verify connectivity, but after I successfully dumped with the Python script, I went back to the GUI tool with my exact same setup and couldn't get a connection.
I used a super cheap CH340 for my adapter, purchased from here: https://www.aliexpress.us/item/2251832482551324.html
For what it's worth, I also attempted to use @b3ncs1's recommendation for a Raspberry Pi Pico. No dice on that one. I tried both firmwares linked to the repository, made sure my wires were connected to the correct pins, different cables, etc. and that did not work for me with the scripts or the GUI tool.
I attempted both Auto and manual options in the GUI tool. It would scan everything successfully, but no response each time.
Those photos are my exact install as-is which worked, I did not have to remove or add any components.