I have CS4 Design Premium. If I do a 'cross upgrade' to CS6 Production Premium, will my InDesign CS4 still work?
Yes your old CS4 application should work fine as it has nothing to do with CS6.
If you’re going to use Windows and Mac, I would strongly recommend Creative Cloud. Through the end of August you can get intro pricing of $29.99/month for the first year and it’s crossplatform.
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