Weirdly, I ordered from JLCPCB and they had from @e-fortier original Gerber file and they sent me back a request to change similar to post #492 but I approved them to make the change and ended up with functional boards. I have at least 1 pair left if anyone is interested PM me and I'll send them out USPS only.

As a side note....
If I did PCB design I'd probably put two three-watt resistors in parallel for the bias resistor rather than one 3-watt , which got hot and melted the cheap clip-on probes from my multimeter (not that I would have thought of this during design). Of course, I left them on for an hour or more. 5 watt is a good idea too. I might also order a multi-turn pot for the bias although the single turn does work. (I biased at .75 volts)
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This is what I use from Digikey.

R1_0.5 ohm 5W.PNG
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As I mentioned earlier, P1 is connected the wrong way. You must put it fully clockwise to have minimal bias then turn it gently counterclockwise to slowly increase bias up to about 1.5A to get about 0.75Vdc across R1. Keep me posted.

You can put back your SMPS if you wish.

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