Please try this:
- Backup your settings.
- Uninstall Opus.
- Reboot.
- Install Opus 11.15.
Do not restore your settings yet. See if the problem is still there first. If it is, it's not your settings and you can restore them.
If it's not in your settings, it's probably either a shell extension installed by another piece of software or something on your system like an unreachable network drive mapped to a drive letter.
Crash, exit or high CPU usage when viewing certain directories
General slowdown or instability investigation steps
That sounds normal. 
Is there a typo somewhere there?