Red + guide laser works on Totem S, but burning laser does not fire

Thank you in advance for your help. I recently purchased and assembled a Twotrees Totem S 40W laser. It moves X/Y just fine, and it shows a red dot / “+” guide laser on the table the entire time. Unfortunately it simply doesn’t fire the burning laser. I’ve tried raising and lowering speed and power; nothing. Same thing in LaserGRBL; movement, red dot, and no laser. Newly purchased hardware from link below, factory configuration.

Engraver (not promoting/selling, this is for reference only):

Pity they have no tech support at that $250 price point, eh?

You’re not kiddin’.