Hi L1ne,
Thank you for the report. I was easily able to reproduce the issue so I have created JIRA report UE-13672. Our developers will be investigating it further and we will post back here with updates as we have them.
As a workaround, I noticed that if you add the overlapped actors to an Array then loop through that array, it will work correctly.
Let me know if that works for you.
Cheers,
TJ