Hi Mike,
Thanks for bringing this to our attention. I was able to reproduce the problem with your suggested setup (XnView), and then was also able to reproduce the problem with a new simple MSI package that I created with InstallShield.
It looks like the capture phase of Repackager worked correctly, but the build phase is not handling brackets correctly.
I reported an issue for this behavior with number #IOA-000058270.
Thanks,
-Ajay