Nice, good job!
Did you try DSM 5.2 5565? That has docker in it ^_^
N0 I have not tried nothing else i.e : If it works, don't break it.
It nags for update, but thats all. No its working perfect, so why bother ?
Its absolutely amazing that an old, old computer, graveyard like can become a super NAS. I mean I would not even have given it to my kids.... but as a NAS it rocks.
I will update when I am sure that everything works, and 5.2 is not generally working yet, so why try ?
Cheers