As far as eating is concerned, yeah, flapjacks and maltloaf, indeed bananas too (but they get beaten up easily); they'll all do you good and you can get them all at a garage if the worst comes the worst (and you're never far away from a petrol station on the route!).
With the creams, there's plenty of them out there - it's whatever works for you. Some swear bygood old fashioned vaseline, some love to spend a fortune on the most up to date concoctions flown in direct from the monastaries of Nepal...
Really, make sure you get loads of good carbs down you in the mornings wherever you're staying. AND make sure you get as much prep done the night before for the next day otherwise you'll spend ages faffing around in the morning (and that get's really frustrating especially when you're tired).
Be prepared to start early in the mornings, it gives you a bit more time to stop and enjoy the views.
Do be wary of the last hundred miles or so - there aren't many trees, for good reason - it's soooo bl**dy windy!!
Good luck!