Don’t delete the mx700 software that you have but you could download this version which was for a rebranded mx800. Install it and see if it works with the correctly built cable. Mx800 had RF ability and that functionality is in this software. It obviously won’t help you in that aspect but may install with all the correct settings.

I looked through the original owner manual above and it did not have any computer settings. It did have the pin out info to build a cable though.

Here is the file link

[Link: files.remotecentral.com]