OK..Hopefully this info will assist.
I can't provide a link because it's running offline, it's not actually hosted yet. A module was added 'attributes_separate_stock_v0-1.zip' which we need for our particular products. This didn't effect the dropdowns and they were working ok post installation.
The 'option names' and 'values' are all present and correct for the products and under 'Attributes Features'. The preview shows the dropdown as you would expect to see it (pause for breath) but...when you look at a product at the front end, the dropdown is there and 'drops' but the values are not visible.
Thanks in anticipation :D