Is there any way I can export the 'who opened' list from the campaign report?, or add the people who opened to a new subscriber list so I can export all details?
I haven't really played around with the API yet etc. but I have a few clients who would like to quickly generate this data from sent campaigns...
I can think of a couple things you can do - see if any of them help:
On the "Recipient Activity Report", choose "Recipients Who Opened the Campaign", and click "Display". On the bottom of the page, choose a format from the "Export these subscribers..." dropdown and click "Go".
Or, you can click "Manage Subscribers", choose a list, and go to "Segments". Click "Create New Segment", give it a name, and add a "Campaign Was Opened" rule for the campaign of your choice. The next time you send a campaign, you can choose this segment on the "Define Recipients" step.