Oops! I think you can put thjis down to my dumb user mode. Although I recreated the shares and added them as the correct name for this user I seem to have had an 'old' shared folder visible. When I deleted the two I had there when recreated the shares again, added them plus the requisite "Mobile sync" property on the folder all is working as it should be.
I seem to be having a problem with shared folders on the current version of ZeXtras mobile. I've deployed the zimlet and added it to a COS for my users but when I add a Shared Folder from another account (or two) there is no sync for those folders and they don't show in my mail client (they do show in the ZCS Web UI) when I refresh the folders for an account. My mail client is an android app named Nine Folders, it's been working fine until this release.
Because of the problem I had with the last version of ZeXtras I wiped all the account details from the client the readded it and did a full sync, everything was downloaded as it should have been except the Shared Folders. I've made sure the mobile zimlet is deployed correctly, it's normally deployed on my COS but I also tried deploying it for a specific user with the same results of the Shares not showing. I don't know if this is a problem with ZeXtras or my client but as I've just upgraded the ZeXtras install I thought I'd try here first. 
What do you need to see from the logs for this?
BTW, I did also try a ZCS restart and still no Shared Folders visible on my mobile.
Further update: When I deployed the zimlet in a user account I made sure it was set as 'enabled', that should show in the user account preferences but it doesn't on my server.