I have Keynote installed on my iPad 1 and have used it successfully a while ago. I now need to make and give an important presentation but when I select the Keynote icon the page changes to a Keynote screen with a grey background and then changes back to the default iPad screen with icon after about 5 seconds. This happen every time. I have deleted the Keynote app from iTunes and re-installed it and carried out a new sync but nothing has changed, HELP!!!!