Has anything changed in the zip plugin in the last, say, 30 days? Files that have been uncompressing properly have stopped. I get and trap the isError event variable, so I know that it failed, but no reason as to why. I'm not sure exactly when it stopped working as I havent been in that part of the code but was doing an end-to-end test and discovered it. Until today, I was on 2017.3100 (just updated with today's build for the google path traversal error)
The files are downloaded from our site, and show a successful download. I have no problem uncompressing the .zip files with winzip.