1. Puybaret, I did it through the terminal by typing "sudo apt install sweethome3d". As far as I know you can also do it in the "Add/Remove software" app. It seems that it's a proper distribution for an ARM processor.

2. UbuntuBirdy, thanks for the help!

3. I think that the problem is Java ...

I've installed SH3D on Raspberry PI 4 (no problems there) but whenever I open the program it's full of black boxes that change when I move a coursor, add a new component or open a menu. Examples of above problems can be seen on these pictures:

https://scontent-waw1-1.xx.fbcdn.net/v/t1.15752-9 ...