You only have two options, right?
So, if you are running it on the same computer each time, you can image recognize each possible popup image and direct PAD based off that. To be honest, I would remove the popup dialogue box and put Success/Error in a cell in the workbook to read from after, but assuming you don't have the permission to do that:
Note: the PAD action "Run Macro" will not work for this if the dialogue box is in the Macro. It won't be able to get out of the macro. You have to run the Macro manually with 'Send Keys {Alt}()wmv', [macro name], and {Enter}.
Loop
If %SuccessImage% exists
Exit Loop (will continue the process)
EndIf
If %ErrorImage% exists
Run Subflow ErrorFlow (create a subflow to manage your error)
EndIf
Wait 10 (seconds) (or whatever interval is appropriate for waiting for your macro to be done)
End Loop
