Marketo reports are useless, I am wondering if there is a report that don't give you time out or an orange screen. What is this "&queryLimit=5000" about, are you kidding?
I'd reach out to support to see if this is related to the issues they were having with one of their datacenters, or another issue related to your account. This shouldn't be happening when you try to run reports.
This only occurs on the summary tab of smart campaigns or reports. There's either a timeout or a flash error.
Ask support.