Thank you for the great feedback! I hope you still found it enjoyable :D
1. The repair hut can be used to repair damaged tiles / buildings. If a tile has less than max health, a health bar appears over them. Using the repair tool on this tile resets the health to full.
2. This was a simple miss by me, thanks!
3. I am aware of this and am working on a fix.
4. You cannot trade anything, which is by design. This should probably be more obvious to the player though. I looked through the code and found the issue regarding not being able to build when workers are less than 0, even if no workers are required. It now works as intended and will be patched shortly. Thanks for pointing this out!
5. You cannot build through buttons, but you can build through UI panels and images. I understand this can be an issue and i will try to fix this.
Thanks again for the feedback!