Resuming the test outcomes as the discussion about side aspects got too long and sort of eclipsed the thread origin :
- There are some UX issues with the installer as:
- add text pointing to a swap-file option if needed
- 'language and keyboard' configurator needs some changes (some already seen to)
-
Elive-center and related .desktop files need some icon changes. (some already seen to)
-
The 'default' browser choice isn't ideal.
No real biggies there, yet ...
So all in all not bad for a release candidate. 
Update
I upgraded 3 systems yesterday. The first was on an SSD over USB with encrypted partitions which I messed up myself because I didn't remember which was which there.
The second was on a USB flash disk but that didn't go well as Grub' didn't get installed on it ... and thus wouldn't boot after that.
The 3rd was an older (3.8.20 IIRC) Elive that ran from SSD but was originally installed with 'legacy BIOS' but I booted RetroWave with EFI.
That last one was caught excellently by the installer. Warning and offering solutions...Very Good!
So that Helix2 Thinkpad now runs RetroWave. 
