It's difficult because A) the process doesn't work at all and your devs now have to implement an entire new script for users to upload or download files that also have the potential to break.
Also, yeah the .zip upload doesn't work at all, not just sometimes. I have been trying every 5 minutes or so for the last hour.
edit : zip upload doesn't work, but Ryan took care of it pretty quick through a support ticket (< 1 hour) and unlike others it seems to be working. Thanks Ryan!