@Shai You’re not alone.
I remember having troubles with the FTP nodes as well in the past (until ~ 2 years ago). Back then I was tied to a KNIME workflow and somehow needed to get it to work, so I used a Java Snippet node with the Apache Commons Net library. You can include arbitrary .jar files in the “Additional Libraries” tab – ideally put them into your workflow and reference them with a knime:// path, so that the WFs are portable (see here). This is fiddly, but at least you have full control of the setup and can adapt the error handling to your liking.
I have since moved on to different tools for these kind of tasks though – when writing the code anyways, there’s not much reason to use a workflow for me.
– P.