Here's the original thread in Corel's forums that I found back then:
In short, it says that Quicktime 7.6.6 was the culprit, and downgrading to plain 7.6 solved it, which worked for me then. I just looked and apparently I've upgraded to 7.6.9 which is current somewhere along the way, probably with some software I've installed. I can say that mine is working 100% as is... Check and see which version you have installed, if it's 7.6.6 or close to it, you might try updating Quicktime. It can't hurt, and you can always use system restore if it doesn't play well with something else...