Bizarre problems local vs remote

I have a really bizarre discrepency between my local website and my remote
website. The whole site works perfectly locally and uploads fine except it
appears to exclude images with rollovers when displaying the page online. The
files are all there and there is no 'missing image' box showing - what is going
wrong as I just can't figure out what I've done? The site is www.loop360.co.uk.
Thanks in advance for any help you can give.