Phili,
I hear your frustration and haven't said anything up until now but maybe you need a bit of tough love? If not don't read on.
My advice is to be 100% totally honest with your doctor about exactly what you are eating & drinking (heads-up: he's not stupid, your not fooling him, just be honest). Take in a full weeks food journal and weigh out the food - don't guess. The slimming shakes are keeping the weight on you - they do not help at all - they are liquid calories and your band doc should be telling you to stay far away from them - NO LIQUID CALORIES.
If you weight isn't going down quite simply you are consuming too many calories for your body. If you consume less calories you will lose weight - this is what your doc is trying to achieve by giving you fills. If you drink slim shakes and eat food that goes straight through the band (crackers) you are working against him, not with him. You need to be eating solid food like chicken/beef (not deli sliced) to really work your band.
Why have you swapped fish & vegetables for ham & cheese (fat) with crackers? The fish & vegetables were probably a much much better option for weight loss. How much chocolate are you eating a week? A 250g block of cadbury is equivallent to about 2 full days worth of food.... how often would you eat a block honestly? (don't have to tell me, but be honest with yourself).
With the change in food choices and other things you have mentioned I think you probably do have 'restriction', but it's the big band type of restriction not the vomit type of restriction you had with the small band.... you don't need vomit restriction.... just need to learn to listen to the new band about when to stop (cause it will let any food through, just a bit uncomfortably). Are you hungry alot??? If you are not hungry are you eating when you are not hungry just because it's "meal time"???
As for exercise, what you are doing with your friend sounds great. You should be able to hold a conversation while you walk (not be too puffed out to) if you are wanting to exercise in your target heart rate to burn fat. Far too many people have dropped dead these last few months in Victoria following the sweating and pushing yourself to the extreme advice - only take health/exercise advice from doctors - remember anything you read here is just an opinion and not medical advice so clear stuff with your doc before you make serious changes.
Sorry to be so brutally honest with you but it's been a really long time so maybe you needed to hear it.