This might sound stupid but I cannot find where you register your pyramid on squarp’s site for warranty and also update info.
+1 on this. Would be useful to add it to my Squarp profile. I think I had to submit it for a bug report some months ago. Maybe give them a shout and ask if they can register for you. They’re quite respondent. 
So how should I register my brand new Pyramid Mk3? Do i have to write to them?
Ive just bought a brand new mk3 in the UK and I too would like to know how I register the product please.
There is no need to register products.
A receipt is all the documentation you really need when it comes to proof of purchase.
For update info, you can subscribe to “categories” on the forum. I just created some dedicated categories for this purpose.
I’m closing this topic, and I’ll make a quick how-to for such subscriptions.