Opus with multiple listers hangs on Windows shutdown

Just reinstalled Windows (XP SP3) on a Thinkpad laptop and of course numerous drivers and software. Everything works great until Windows shutdown/restart, then Opus hangs (wont close) and prevents shutdown. I get a program error message - '0xc0000005 occurred in thread 'dopus lister' at address 0x017514a0'. Also the Windows 'End Program' dialog appears, and if I click the End Program button then Opus closes and shutdown/restart continues as normal. The interesting thing is that this happens only when more than one lister is open. I normally use 2 dual pane listers from startup to shutdown, but if I close one of them (and leave the other open) then all will shutdown with no problem.
In other words, Opus only hangs on shutdown when there is more than one lister open. Anyone have any ideas about this?
I am told by support that it isnt an Opus issue, which is odd because its Opus that will not close. It may very well be something else that Opus is having a problem with, but its Opus that will not close when its supposed to.

My guess is that a shell extension is crashing inside of Opus if more than one instance of it is shutdown at the same time.

Can you think of anything you've installed which had added file context menu items, or which adds columns or custom thumbnails to Opus & Explorer?

You can use ShellExView to list, and disable/enable, the extensions you have installed. I would experiment with them as a starting point.

You may also find it useful to load Process Explorer when the crash happens, but before dopus.exe has been killed. Then select dopus.exe and push Ctrl-D to show the list of DLLs loaded in the process. Click on the Base column to sort by address and see which DLL has the base which is largest while still being below the crash address. -- That doesn't always indicate the guilty component but it often does.