OK - Done ... and both Cloud and Bluetooth connection to Scubapro G2 both work (haven't pushed my luck by trying USB)
However, I didn't know how to install the PPA other than through Software Manager, and Software Manager would only find and offer to install the Flathub version - until I removed FlatPak capability first :
sudo flatpak remove --all
followed by
sudo apt-get purge --autoremove flatpak libflatpak0
and
$ sudo rm -r /var/lib/flatpak
After that, Software manager found the PPA and all went ok.
I'm sending this before rebooting - if the system goes pearshaped because the first command removed -
ID Branch Op
1. [-] com.dropbox.Client stable r
2. [-] org.gnome.Platform 43 r
3. [-] org.gnome.Platform.Locale 43 r
4. [-] org.freedesktop.Platform.openh264 2.2.0 r
5. [-] org.freedesktop.Platform.GL.default 21.08 r
6. [-] org.freedesktop.Platform.GL.default 22.08 r
7. [-] org.freedesktop.Platform.GL.default 22.08-extra r
8. [-] org.freedesktop.Platform.VAAPI.Intel 21.08 r
9. [-] org.freedesktop.Platform.VAAPI.Intel 22.08 r
10. [-] org.freedesktop.Platform.openh264 2.0 r
11. [-] org.gtk.Gtk3theme.Mint-Y-Aqua 3.22 r
12. [-] org.gtk.Gtk3theme.Mint-Y-Dark-Blue 3.22 r
13. [-] org.kde.Platform 5.15-21.08 r
14. [-] org.kde.Platform.Locale 5.15-21.08 r
- then I will report back on another computer! However that pans out, I am very grateful for your help
Keep safe,
Charles