Recent .ova + disks from an older version = Ok ?

Hey I’m back into Whonix after a while, I’ve brought out the system disks I had back then, and now I’m trying to rebuild my machines in VB.

Can I import images of Whonix 13 and then point them towards those disks ? They were Whonix 11 or 12 disks, I can’t really remember.

I’ve tried without importing images, just by pointing VB towards the folder where the VMs are, but no machine appears in the VMs list in VB (I don’t know if that’s normal or if it is a matter of not enough privilege to access the content of that folder, it doesn’t reside in the system disk. And empty list as well for sudo virtualbox + same folder path).

Host is Ubuntu 17.04 btw

EDIT: If machines are working right, and if my disks are from Whonix 11, then I first follow these steps

and then these

right ?

Okay, it went rather well. Making the .ova and disks files work together just needed a bit of editing of the VirtualBox.xml file and fiddling with the Virtual Media Manager, and then all was ok.

I then followed the steps needed for an upgrade to v.13, and I seem to have succeeded.
Whonixcheck displays all green lights and sanity checks results are fine, but how can I be sure that I really succeeded ?

-Whonix packages dependencies are version 3.4.2-1, that’s good?
-One thing I’m not sure about: the repository for updates is the Jessie repository, should it be that one ?
-Is there something else I need to run or test to verify that I’m all good ?

(Actually, I was like sure that it was going to fail, after one year and a half without having touched Whonix. And now, the simplicity and smoothness of how it went is just making me doubtful that all is really in order.)