cpr to txt conversion covers the export of Cubase project (.cpt) to Steinberg LM-4 sound bank format, and not some kind of text conversion actually.
Cubase projects are tied to the original software, so you need access to it to attempt export of any kind. If you do not have access to the tool anymore, you have to either find someone who does or perhaps reach out to the online community and ask for export from your project file. Cubase also offers trial version, but that might not help everyone.