We've tried altering the programs in the blocklist, and it doesn't seem to make a difference.
The furthest we've got is by adding the registry entries [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PCHealth\ErrorReporting\DoReport] and [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PCHealth\ErrorReporting\ShowUI] and setting them to 0 - this works some of the time (it works all the time if the exception comes from managed code), but if the exception occurs in some external code, for instance a windows media player codec, then the dialog still appears.

The only way that worked for me to disable the error reporting dialog completely was adding a DWORD setting with a value of 0 in:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting\DontShowUI]

[Start] [Run] [Regedit]
Registry Key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PCHealth\ErrorReporting
Modify/Create the Value Name according to the Value Data listed below.
Data Type: REG_DWORD [Dword Value] // Value Name: DoReport
Value Data: [0 = Don’t Send Reports / 1 = Do Send Reports]
Exit Registry and Reboot