its another so called firewall defender that claims to do things but doesn't do anything. the reason its doing all that is because the files are not scan it will block any file no matter what. the reason steam games have no problem is because bitdefender whitelist them, meaning anything even a virues on steam can pass you firewall.
the best advice i can give you is uninstall it, there are too many "firewall defenders" that just block files that are not trust worthly with the company.