Background - Netgear Readynas nv2+ and 4 x 3Tb drives

Had it roughly 4 years and recently just bought with assistance of folks on this board - Synology 1815+ as a replacement. 

Just this week the HDD in the readynas started to go - what are the chances !! . Was getting erros in my inbox then a ' drive is died - volume unprotected emails' - one of the infamous seagate barracuda 3tb that now appear to have a very high fail rate and a class action lawsuit happening.  Powered down nas while i decided what to do.

Decided to scrap the drives but would salvage some key files from them (older video files).  NAS is Raid5 ( XRAID2) so assumed I could still access it even though i now had no redundancy. Powered Nas back up and it was working fine but slow..Then it got very slow, started throwing me some more drive errors then got even slower. It hung so I powered it off at mains as the power button wasn't reacting to anything. After several bootup hangs i finally got it running again. Problem now is although I can see the shares on my desktop network and also using Raidar( Netgears software for the readynas) which also lets me browse them I now can't open them and get a network path error in windows. 

I also received a couple of emails from the readynas saying it was ' missing shares and this is likely due to being unable to access data" etc..

This is IDENTICAL to the problems I had when had a power cut in the first couple of weeks of owning it and was syncing the drives and raid. It was powered down then came back online with the same emails and same symptoms. Shares were there but couldnt be accessed etc.  Turned out the unit locks the HDD's during resync and a lvl 3 tech unlocked them after fluffing around for nearly 2 weeks with lvl 1 and 2 switching it off and on etc.  I am 95% sure this has happened again with me forcibly having to power it off again and the drives are ' smart locked' as i was previously informed.   I kept a copy of the transcript and the relative snippet below when i asked him what I would do if it happened again.  Can someone assist me in basic terms how to do this.  We had to reboot the nas in tech mode which is easy enough. It's the rest of it and how to access 

1. install ReadyNAS enablerootSSH add on.
2. login to the NAS via SSH
3. check the disk if it is locked by doing:
a. # cat /proc/partition
b. # hdparm -I /dev/<disk label based on partition table>
c. unlock the drives using

hdparm --security-unlock NETGEAR /dev/sda
hdparm --security-disable NETGEAR /dev/sda

that is the procedure to unlock it.

I can pay netgear either $50US for a one off help or $90 US for 6 months of help and actually have no issue doing that however having read hundreds of reviews about their paid tech support service, most of them damning,  I'm hoping a DIY approach will have better results at much lower cost.

Cheers for your ideas. 

Ged