This command line tool removes DRM from magazines in your digital Zinio library. For more details visit my blog post Removing Zinio DRM.
No, you don't—this tool skips issues that you have already downloaded. It will only download the magazines that are not present in your download folder.
I agree that this would be a nice feature, but I will not implement it, mostly because it would be complicated to use from the command line. Again, you don't have to download the whole library each time, so this feature is not essential in my opinion.
Zinio DRM removal tool is using dep for managing dependencies. If you want to build it from source, you have to install dep first, and then run the following command in the zinio directory:
$ dep ensure
$ ./zinio
Usage of zinio:
-email string
Account email
-password string
Account password
$ ./zinio -email user@example.org -password secret123