My ( video ) downloads stop saying completed under 32 MB ( sometimes 15 , 16 , 17 MB ) when VPN is on. The download finishes successfully when VPN is off.
Another option I tried is starting with VPN off , waiting the download to continue till 100 MB and then set VPN on. This also does complete the download successfully.
I observe this since about mid May 2017. Earlier there was no problem.