Come across one of the most annoying problems this evening. after mocking up a standard html page showing a google map on it, i got it exactly how i wanted it then i moved all the code over to a ASPX page.
As soon as i run it there was no more map showing.
After endlessly searching i found out that changing the Maps DIV width and height from a percentage to a Pixel, i could now see the google map.
Have no knowledge why this is but thats what solved my issue.
Hope this helps someone...
Jonathan