Make sure you have "Allow Exposé, Dashboard and others to use the screen" in keynote preferences under Slideshow.
Then, before you slide over to Safari, press the "F" key to pause the slideshow. This prevents the slideshow from disappearing.
You can then slide over, or use Mission Control, etc without affecting the slideshow.
There is a bug here, to go back to the slideshow you have to slide back to it or click on the desktop in Mission Control; you can't click the Dock icon or Cmd-Tab back to it.
(Clicking the dock icon / cmd-tabbing will just hide the dock and menubar but not take you back to the presentation)
Also: When you get back to the slideshow, the first key press or mouse click unpauses the presentation, so you will have to click / press again to advance to the next slide.
Side note: instead of having keynote and Safari on separate desktops, you can have them both as fullscreen apps. This hides the Dock and Menubar, so when you show the web page, there is more room for it.
If you do not want (or can't) get the app out of a backup you can extract it from the installer.
Download the Airport Utility 5.6 for Lion and move the file AirPortUtility56.pkg contained within the dmg to your ~/Downloads folder. Then in a Terminal window do :
$ cd ~/Downloads
$ pkgutil --expand ./AirPortUtility56.pkg ~/Downloads/AirPortUtility56
$ gunzip -c < ./AirPortUtility56/AirPortUtility56Lion.pkg/Payload | sudo tar -C / -xvf - "./Applications/Utilities/AirPort Utility 5.6.app"
The app works without issue on Mountain Lion in my limited testing so far.
If you wanted to mod the package to skip the check, if you want to easily install the package on multiple macs for instance, here's what you need :
A tool called "Flat Package Editor" to modify the file called Distribution in AirPortUtility56.pkg. To get that tool download the "Auxiliary tools for Xcode" from the Apple Dev site. It's hidden in PackageMaker.app/Contents/resources/Flat Package Editor.app. With it you can open the pkg directly :
Just drag out the Distribution file and remove these lines :
// Less than 10.8
if(-1 != system.compareVersions(my.target.systemVersion.ProductVersion, '10.8')) {
my.result.type = 'Fatal';
my.result.message = system.localizedString('ERR_OSHIGH');
return (false);
}
Drag the new version back in, delete the old Distribution and save.
Best Answer
I presume that you're trying to purchase iWork from the App Store.
You can purchase a physical copy of iWork '09 and install it.
If your Mac doesn't have a disc drive, you can use Remote Disk to do so. You'll need access to another computer (either Mac or Windows) that has a disc drive. Apple has complete directions for using Remote Disk here.