I don't have a copy of Office on the Mac I used to convert the old Apex Club files and most were lacking a suffix, meaning I had no idea if they wore .cwk, .doc, .docx, .txt or .rtf. SO I added .odt to each filename and used LibraOffice to open each one & save it to .doc format.
There was one document that needed a lot of reformatting of the paragraph structure, so I modified the new .doc file using Writer 2 app which I'd quite forgotten I had.
And in case my friend was unable to transfer his text message Dropbox link, I sent him an email with a zip file of the Dropbox folder concerned. I even took the trouble to use CleanArchiver app to zip the email attachment.
If you're not familiar with CleanArchiver, it makes sure that the extra little associated invisible Mac-only files that only serve to confuse PC users are NOT added to the zipped file.