Opening With Associated Program

I have a new problem. I did not have this problem before today on the same computer and OS (Vista x64). However, I formatted and re-installed Vista clean today, and the problem has been present since. I double click on a file that does not have an association, and set it to always open with the program I want via the open with dialog. If I then double click on one of these files in Windows Explorer, it opens in that program with no problem. However, if I double click on this same file in DOpus, it shows the open with dialog, and I have to click OK on it. The program I selected for it to open with is selected in the open with dialog, but why is the open with dialog always showing? Thanks much.

Opus is not currently compatible with Windows Vista. This issue will be addressed in the Vista-compatible version.

The thing is...this did not happen on Vista before the format... So, I assume there's just something that needs to be changed. Do you know what it is or why it is occurring now when it did not before?

No idea sorry, as far as I know it's a confirmed problem with Opus 8 under Vista. It certainly behaves that way for me.