Export to Flash-8 feature has been discontinued from Cp4.
From now on Captivate will most probably be supporting the latest 2 versions of Flash only.
CS3 and CS4 as greyed out options: because they are not installed on your machine.
I have the oposite issue. I am using Captivate 3 with Flash CS4 so I am unable to export project to Flash.
Unfortunately there is no way I'm aware of for Captivate 3 to export to Flash CS4. Flash CS4 arrived after Captivate 3. If you want to export Captivate to Flash, you need to upgrade your Captivate.
If this is a one off, perhaps you can install the Captivate 4 trial, open your project in that and export to Flash that way.
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Thank you for your response,
I was afraid you would say that and I do believe it to be true.