Delegated Portal Content Admin

I'm trying to configure delegated portal content administration. Here's what I've done so far:

I've created my own role called 'Delegated Content Admin', which is based on the supplied Content Admin role, except all worksets and iViews except for 'Portal Content' have been removed. The role has been given similar access to the PCD, except that permissions to some of the Wizard iViews (such as the ROle Wizard, Workset Wizard, etc) have been removed. There were also some permissions granted to a few Security Zones.

I've then created a group for the specific set of users, call it 'Project Content Creator'. This group has the 'Delegated Content Admin' role. The group also has full control access to a specific section of the PCD.

This all works great - the user's canonly see a part of the PCD, and they can only create iViews. This is just what I want.

However, we also have a BI component where Iwant these same users to be able to publish BI content as iViews. Using the BEx broadcaster, then can select the PCD folder where they want to store their content, but when they try to execute the publishing step, they get this error:

Error while instantiating an iView descriptor

In the logs on the portal, I see this exception:

A message was generated: 
ERROR
Error while instantiating an iView descriptor
com.sap.ip.bi.broadcasting.runtime.BroadcastingException ErrExportToPcdInstDescr
Log ID: 001CC4EE6212008200000010000068DF000449E6FC5ED587
Message: Error while instantiating an iView descriptor
Stack trace: com.sap.ip.bi.broadcasting.runtime.BroadcastingException: Error while instantiating an iView descriptor

Has someone setup delegated content admin where BI broadcasting is involved? I think I'm missing a permission somewhere, but where?