Ok, I managed to get Deepin to detect my SSD by including the option "all-generic-ide" at boot-up.

Deepin 15 installed fine, but that is it!  Although I encounter the same problem (SSD not detected) on rebooting, the 'all-generic-ide' option fixes things - but Deepin still crashes, either telling me a user "MDM" is not found and to reconfigure MDM and reboot!  Or else I see lots of "OK" messages followed by a big "FAILED" message in red!  When the 'MDM' error occurs, I do get to a login screen, but it keeps asking me to re-enter my password!

My biggest failure yet with Deepin.  Any suggestions?

Well, I concede defeat on this.  The first OS that positively refuses to run on my old laptop - maybe it's too old, and it's a driver-issue!

I tried the same 32-bit installation a my 64-bit desktop pc and it installs & runs without a problem.  One bizarre thing I found was that the installer wrote the grub boot loader to the USB drive I was installing it from, so that it wouldn't boot with out the USB-drive plugged in - which took me ages to sort out.  I have encountered a few more problems,  but for another thread!

Sorry to hear difficulty with old laptop.The installer does have a advanced mode I use to make sure grub goes where I need it.

Yes, I switched to advanced mode during installation but was more concerned about selecting the right install-partition, so forgot to check where grub would be installed to.  Deepin's installer installing it on the installation-USB doesn't seem a sensible 'default-location' though!