I would have to say it somewhat depends on what you purchased. If it's an upgrade, often it is expected that you uninstall the older version before installing the new. I'm not sure with Captivate if that will have any effect or not. I can say that I have Captivate versions 1, 2, 3 and 4 all installed on the same PC. So I know they may peacefully coexist.
Personally, my vote is to leave version 1 installed alongside version 4. Sometimes it's helpful to open a project in each version for the purpose of copying and pasting from one to the other.
Hopefully this helps... Rick
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