error message once i attempt to install iBook Author on my Mac Pro
Yes, without a more current OS X, you will not be able to use iBA, sorry.
Do you know which MacBook Pro you have?
The thing is, you have OS 10.6.8, but you need at least 10.7.4 - The latest version is 10.8.2. You can go to the App Store and ugrade to 10.8 - It's called Mountain Lion and then iBooks Author should install fine.
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