Finally I was able to complete the first (beta) demo of chaostower.
You can find it in the download section.
Currently there are 6 levels (+ Tutorial) available in the demo, showing some basic levels.
In the last level you have a lot of items and money to play around.
So it is worth playing the whole demo.
Please note, this is still a beta version.
If you encounter any problems, please let me know.