Can't enable plugin in Affinity 3.0

[leszekmp]

Latest version of Affinity (3.0.2.3192) installed. Followed the instructions to the letter.

• Opened Default plugins folder from Photoshop Plugins settings
• Copied file and folder into the above
• Restarted Affinity; plugin did not appear
• Created new plugins folder, copied gmic file and folder there
• Added that folder to the Photoshop plugins settings
• Restarted; filter not there

I have put other Photoshop filters into the Default plugins folder, and they do show up. No idea what might be wrong with gmic.