"An error occurred processing your request." on Quick Task Channel on process dashboard

I have a process dashboard that has quick task channels displayed.  When I'm logged in as a Sys Admin, I can see all of the selected quick tasks, but when I log in as a basic user, I get the following:

Here is the channel configuration: 

When I check the appserver log, I see the following (2 separate items): 

[[ACTIVE] ExecuteThread: '20' for queue: 'weblogic.kernel.Default (self-tuning)'] ERROR com.appiancorp.ap2.p.quicktask.ViewQuickTaskPortlet - Could not retrieve quick task design information.
PrivilegeException[null=>null]: Insufficient permission

[[ACTIVE] ExecuteThread: '20' for queue: 'weblogic.kernel.Default (self-tuning)'] ERROR com.appiancorp.ap2.p.quicktask.ViewQuickTaskPortlet - java.lang.NullPointerException
java.lang.NullPointerException

The process model and process security both include the user's groups. The only change I made recently was to remove a quick task from the model being used for the channel (the quick task was not one of the selected quick tasks in this channel) and remove one of the channels that did reference that quick task (not the channel in question).