How can I backup to a Zip file/s on an FTP server?
Using the New Profile wizard simply create a new profile and specify that you want to use an FTP server and Compression.
You should note that for individually-Zipped files, this method creates an encoded Zip name (commencing 'SBZ!...') which is used to store certain parameters - of the file inside the ZIp - so they can be read/checked without needing to download & open the Zip to find out (Zips cannot be opened across an FTP connection, and would need to be downloaded first).
This means that such Zips can only be automatically Restored by using a Zip-to-FTP profile in Restore mode. If you move such Zips manually to a local folder, and try to use a normal Compression profile (i.e, not 'to FTP') in Restore mode, it will fail, because the filename inside the Zip is not in the same format as the external Zip name. An ordinary Compression profile expects & checks for this, and is not set up to expect the coded version used in Zip-to-FTP.
The contents of such Zips can be manually extracted via a 3rd-party Zip utility, but the process cannot be automated via SyncBackPro or SyncBackSE if the above is not adhered to.
This does not affect files compressed into a single-Zip. However, you should note (as per the Help, and as per the prompt when creating such a profile) that the single-Zip still cannot be read/queried 'across' the FTP connection, and is thus always replaced and is not updated.
You can optionally use your local drive as an intermediate storage device.
Create two profiles: one to backup/sync your 'live' files (data) with the ZIP file/s created & stored in an intermediate location, and one to backup/sync those Zip file/s with the FTP server. Next, create a group profile and put both of these profiles into it (so that a Zip file or Zip files are created/updated by the first profile, and the second profile uploads the Zip file/s to the FTP server). Now, run/schedule the group profile. You may need to experiment to get the settings correct.
Always test first using files you can afford to lose!