Report including tag triggered by button is not working

Hello. Seems like I will be here quite often...

I have set up a Report (including tags), and configured a button to trigger it. But I can't get any output.

I can select to produce a PDF or simply save to disk, but I am never asked for a file name or location.

I have followed exactly what it says in the help. The help does not seem to mention file names or locations, apart from the syntax required by the operating system.

Do I have to include the full path to the .rep file? The help states the filename cannot include spaces. the path however, will contain spaces as that is how windows works. If I specify a path to the .rep file, will the report output be saved in the same location?