access denied to data on my ReadyNAS NV+ running 4.1.14 after a changed security mode to "user" mode

I suddenly had access problem connecting my imac and windows 7 computers to my ReadyNAS NV+ data.

I thus read the latest manual which said that the default security mode of "share" is not compative with the latest versions of windows 7 and apple OS X.

As recommended i changed the security mode to "user" mode which now requires user accounts to be set up for access.

I would have liked to add all the user accouts and passwords form each of the devices on my network to give them access to the NAS. However all the devices on my local network have user accounts with a space like "John Smith" and the READYNAS will not accept a user name with a space.

I thus set up two new user accounts but without a space - like "johnsmith" with a password the same as "John Smith" on the devices. Both users are in the default "users" primary group

I could not gain access to the existing shares. However I did manage to set up a new share using all the defaults and with public access (and thus the "allow guest access" is ticked in the first section of the share action restrictions). This has worked for a while but I am currently also restricted form access the new shares as well. I have tried using the "John Smith" as well as the "johnsmith" user names but I am denied access. I then tried the nuclear option of using the advanced options in the share and changing the share folder owner to johnsmith and the share folder group to "users". I also ticked the "Set ownership and permission for existing files and folders in this share to the above settings" box and the "Grant rename and delete privileges to non-owner of files"

I expected that this would allow me access as a guest or as a user "johnsmith".

However I am now denied access to all my data.

I can use windows explorer to see the NAS and the folders but cannot access my data.

I can access the ReadyNAS using raidar and the admin access. I can also set up a new share in the user secuity mode with all the default settings.

However I now cannot access a new share or the old shares

I have wasted many hours. This has all been caused by the default security mode being not compatible with the current windows 7 OS for windows and apple OSX.

I have had two occasions recently when the NAS was on but I could not find it using raidar. I also could not switch it off using the power button on the front and had to resort to unpluging the power restarting it to get access back.  Have I perhaps got a hardware problem?

What I would be really grateful is advice on 

1 how to set us and get access to a new share

2 how to get access to the data stored in the old shares

I dont need any clever security just something that works with the other devices on the network that need to access it to backup their data

Regards

Gordon Webb

PS the unit has 4 2 tb disks in - all compitable giving it 6tb of raid protected data. It even warned me of a SMART test failure recently and I was able to successfully replace the smart test failed drive with no loss of data.