Crash reports are not sent to us automatically. If Opus catches a crash it will create a crash dump which you can zip and email to leo@gpsoft.com.au if you want us to take a look at it.
The problem with Explorer Replacement could be due to compatibility mode being set on the Opus program files incorrectly.
First, disable Explorer Replacement mode.
Then please follow the steps here to check that compatibility mode is not turned on for dopus.exe. If it was on, please turn it off, then fully exit Opus using File > Exit Directory Opus, then restart Opus.
You can then turn Explorer Replacement back on, which should apply the settings correctly for the version of Windows you're on.
Problems can also be caused if Opus is running as administrator, but it's less likely to be that if the Desktop double-click method is working OK, as that would usually be broken as well if that were the problem.