I've previously asked the question, why FME Server doesn't use something like "Shared Folders" in FME Desktop. The simple answer was, that it doesn't support such novelties, so I have to manually copy the needed files.
But it's actually even worse, I just found out.
I'be built numerous custom transformers with FMX and Python, and I can easily upload workspaces using these to FME Server, but the custom transformers are ignored, and thus FME Server can't find the neccessary Python files to run the workspace.
I thought that I needed to copy the Python files, which are in a single shared location wrt. Desktop (<Shared>/Plugins/Python), to a similar fixed folder in the FME Server transformers search path.
Alas this didn't work, and it occurred to me, that engines only use this to find FMX files.
And (according to the job log) the only dynamically added folder to the Python search path is the folder, wherein the workspace (FMW) itself resides. NO common/shared ground for Python code, it seems.
When I added the transformer's Python code file to this workspace-folder, it worked. But this is a bad situation.
I think it would be a great idea, if FME Server had a single ressource folder for Python code files, that were also added to the engine's Python search path. That way a single folder could be used to store all Python code files regardless of which workspaces that uses them.