Problem: avast 2015 for macdo not update

Hi.
I install Avast! Avast Mac Security 2015 v10.8(43825) but virus database do not updates. When i try perform updates appears message . In log:

Connecting to repository http://download.ff.avast.com/mac/vps
Downloading vps.lat…
curl: (52) Empty reply from server
Downloading vps.lat… (retry 1)
curl: (52) Empty reply from server
Downloading vps.lat… (retry 2)
curl: (52) Empty reply from server
Warning: Download failed [exit code 52]
Cannot download. Perhaps we are offline?

I can’t access avast pages in my country! I have to use Shadowsocks to login this bbs. now,I can access google for Shadowsocks,but update my avast!

Sorry,My English not good!!!

You have to consult Shadowsocks documentation to know how to set it up so other programs (not only browsers) that access the internet (Avast updater) can use it.

You’ll likely have to set something in : System Preferences > Network > (Your connection) > Proxies

I keep getting the same error messages and am not able to update. I also couldn’t find any option in preferences where I could set up my proxies. Any help - much appreciated! Thanks!