Heya, I’m the guy who put this together. Let me know if you have any questions about it! I’ve had the setup for about a month now and absolutely love it.
How is the panel? Do you have any uniformity issues? In total, I've tried 7 units of LG 5K UltraFine (27MD5KA-B and 27MD5KL-B). All had [1] uneven brightness (visible on white background) and backlight bleed. Some of the units also exhibited tinting and/or faint vertical lines. I couldn't swallow these issues for the price that I've paid. Now I'm with Dell U2720Q, but I miss the high PPI of the 5K.
Frustratingly this was a native iMac feature "Target Display Mode" in 2009-2014 but they dropped it from the 5K model: https://applerepairstation.co.uk/Technical%20Desk/use-your-i...
Can you link to the supplier of the driver board?
How did you go about determining the board was ok to plug into a shinny new panel?
My previous experiences with Aliexpress where a bit hit and miss. Either with issues of using obvious counterfeit parts or batch quality issues (order 100 and 70 are OK, etc.).