I have tested this on my Win10 laptop and it works (although I have not played extensively using it). Possible fix for Win10 users:
http://steamcommunity.com/app/521800/discussions/0/133262848297436093/
"In your steamapps, CO2 folder find CmdOps exe, right click and in compatibility tab, choose:
Override high DPI scaling behaviour, scaling performed by - System (enhanced). "
http://steamcommunity.com/app/521800/discussions/0/133262848297436093/
"In your steamapps, CO2 folder find CmdOps exe, right click and in compatibility tab, choose:
Override high DPI scaling behaviour, scaling performed by - System (enhanced). "