Interesting idea, but I barely managed to understand a few words except for the numbers to complete the puzzle, and then I rescued the alien. Felt a bit strange as I thought the one I had to rescue was Hep. But then again I barely understood what she said.
Playing full screen made the UI a bit wonky since I couldn't click the X button and the game seemed to softlock. But outside of full screen it was okay.
I didn't hear any soundtrack outside of the button click, maybe some sounds when the alien spoke (just gibberish talk like in Banjo Kazooie or Animal Crossing).
The intro was nice, and the graphics albeit simple were easy to understand and cohese.
Overall, I liked the idea of discovering the alien language, just wish it was a bit more fleshed out.