What you're trying to do should work, so it's certainly worthy of a bug report. Before you send one in, though, see if any useful information is revealed by the debug mode discussed in this FAQ. If you find anything feel free to discuss it here before sending in a report. We can test whether the same thing happens on other computers, Vista, etc.
By the way, if you're using Opus then you don't need additional tools to manage junctions as they're built-in. For more details, go to the Opus Raw Commands section near the back of the manual and look up the Copy command's MAKELINK argument.