The answer is quite simple, in the logs page of your Smartconsole (Just open any domain) and click the New Tab or the + if New Tab does not show. In the left column select Reports the list you will see shows the standard reports that are available. Now click the Network Access reports and goto the Actions button top middle and select Clone from there, name it with the first domain that you want to report on.
Now double click the name and the report will open, in the right top there is a dropdown menu button that shows Edit, select it. Now rename the reports' title with the Domain name, so when you run it you know which domain it comes from.
Now in the right top select the dropdown again and select edit filter.
Add a row by clicking the plus on the last line and search for Domain Server and enter the name of the Domain itself in the field. Not the name of the Domain management server (CMA).
If you have not done so already you will need to add all domains to the SE server and the Correlation Unit via the old client, on the New Tab page in the bottom left you will find the link to it.
Hope this helps getting you on the way, I'm sorry I did not have access to a system while I was writing it up or I would have added some pictures as well.
Regards, Maarten