Hi Jochen,
The requirements you have mentioned in your query can be taken care of at Design-time itself.
Lets see them one by one:
This can be handled at design time. Go to the properties of the task for which you do not want the user to receive email notifications. In the "General Information" section of the task, you will see a checkbox for notifications. It would look something like this:
Keep this option unchecked to stop receiving the notification for task allocation to Potential Owners.
Also, in your NWA, make sure these properties are false for the service application "tc~bpem~base~ear":
Now coming to your second requirement:
For this, simply create a role on the portal for the people who are authorized to receive these emails. For example, you can create a role called "ReceiveEmailRole" and assign it to 5 people.
Then, when you want to send the email notifications to these people only, you can write the following expression in the "To" tab of the Notification Activity properties at design time in your BPM process:
getPrincipalByUniqueName("ReceiveEmailRole","role")
Doing this will trigger the email only to the users who have this role assigned to them.
Thats it. You are done. This should resolve both your requirements.
Hope I could be of some help.
Let me know if this works for you.
Regards,
Sid.