Прочитал Xenonauts Development Diary:
> Our choice of engine was the single worst decision we ever made. Playground SDK 5 is a 2D engine primarily designed for casual browser games such as Diner Dash. It is not supported by its developers, does not include the source code and is no longer even available to download.
> (We also could have dumped the engine at any point any started over in an engine like Unity. In retrospect, this could have been a good idea.