If we're talking about the updater, I haven't been able to use it successfully for several versions now and had to redownload the whole game.
Specifically, the hash verification fails after the patching is finished. The hash verification pre-patching works fine. Trying multiple times doesn't help. Redownloading the updater doesn't help. The same files fail verification each time I try to re-run the updater. The files that fail are different for each version, though.
Redownloading the whole game works so I haven't been complaining, but my internet is bad so having to wait several hours to play the new version every two weeks is annoying.