Hey Jan!
This is most likely an issue with the servers on Itch.
You can grab the latest free version on our Patreon (8.0.3 - It'll drop on Itch later on) which has a few mirror sites you can choose from here: https://rift.ink/43QZB9R
You'll need a Patreon account, but they are free to create if you don't have one already.
Hope this helps!