No technical problems except for fulscreen being 480p, but thats just extra. Most gam fail to go this far anyway.
This is the best of each genre, I dislike this genre.
I enjoyed the game the difficulty was well placed, altough it could be higher.
Wave 7 is fine, you probably failed too much to be prepared.
The game doesnt have difficulty so some are left behind.
It's not difficult, insane or stresful, I found it very relaxing at all times.
The blure left behind enemy healtrails could be diminished, or atleast give option.
A useful ingame faq would be great.
For what it is: 96/100
Otherwise, It's probably just not so much your game.