Thank you very much for everyone's help. For that particular file - I did what MrTom mentioned and it worked perfectly. I have tried this with another file, but when I double click on the layer (from the main file), a new Photoshop window opens for that particular layer - however, this does not look as though it is a smart object - when I double click on it again (expecting Illustrator to open), it only brings up the 'Layer Style' dialogue - any ideas?
I really do appreciate the time that people have taken to help me. I'm thinking about the possibility of upgrading my Photoshop version now - might make things easier.
I really do appreciate the time that people have taken to help me. I'm thinking about the possibility of upgrading my Photoshop version now - might make things easier.