I got a similar issue when trying to generate the BizTalk Orchestration Profiler report. The error message was "conversion failed when converting string to datetime ...".
Looking at the datetime fields in the Orchestration Profiler UI, I noticed that the dates were being displayed in French format.
Changing my regional settings to "US" helped me solved the problem.
I guess that the Orchestration Profiler does not take into account the machine's culture while formatting dates. Hope that this bug will be corrected in a future version.