Hi Emilia,
We designed the game for a fixed aspect ratio. Make sure the resolution matches that aspect ratio. See your second screenshot. Furthermore, is your screen large enough for a height of 1920px ? I would not be able to play your game on mine because my screen is just 1200 px high.
Regarding the UI being out of place, take a look at the manual and try to adjust the anchor presets and pivot points in your game according to your needs.
I hope this helped. 
See also:
- Forum User Guides : How to mark a topic as solved