I created a YouTube video on my way of resizing posters to the correct aspect ratio.
Way too difficult to explain in text.
Images used in video are linked in the description below so you can follow along.
Trello update: The last weeks we've been improving the terrain generation and we've also put some effort into making landscapes smoother in general (to avoid bumpy terrain). Apart from that, we've also been working on new building tools. You find more information on Trello, but also expect an announcement about the recent changes soon