Garden house - What size and what kind of ground?

So, a few weeks ago we built our garden shed (wood, wall thickness only 14mm) including an attached roof on the paved area prepared for it (Arena paving stones in 5 cm gravel bed on 20 cm compacted crushed stone). I spent ages thinking about the fastening beforehand, but since it now seems sufficiently heavy because of its weight, I didn’t do anything further. According to the delivery note, the material has a total weight of 310 kg...

It’s still standing ; - )
I hope it stays that way!

How secure is the part against slipping? And how did you solve the transition from the wooden side walls/beams to the pavement? There's nothing directly on it, that would rot soon.

The house stands all around on these rubber granulate pads...

A Google search reveals at least one damage event:

Severe storm over Waldbröl. Several garden houses collapsed on the parking and exhibition grounds of the company Cronrath, landed on Wiehler Straße, and partly flew to the opposite car dealership Zielenbach.

Therefore, anchoring in the ground is already advisable. The storms are not becoming less frequent ...