Well done, Nick Webb 1 – that definitely looks the bizz.
Apart from driving a 1.5kW (2HP?) motor with 4 grub screws (I think I would have sourced a suitable tapered coupling) it looks as though that has very neatly removed the ‘weak point’ of these machines with an improved drive.
Obviously not cheap, but likely a lot cheaper than (almost predictable) further motor/control board failures if the machine were to be driven with a good load at low speed.
Now, if only the manufacturers would go that way my opinion of these machines would be very much improved. The old saying of ‘buy cheap, buy twice’ has been addressed in your instance. I reckon that second drive on your mill will prove to be far better than the original.
My machines all have mechanical speed control (continuously variable or by gearbox) so easily effectively operate at slower spindle speeds. How are you finding yours at slow speed? Like, does it need the extra cooling? A reasonably easily swapped two-speed pulley system might be the optimum for your drive?