We've received more information on this problem and boy we're not alone.  One developer on the support forum has a 250,000 person userbase.  Man is he screaming for an answer!  The problem is that it also seems that the developer needs help and assistance from Microsoft to figure this all out (read "this is gonna take awhile").

In the meantime there is a work-around see below:

You need to uninstall "Windows XP Hotfix - KB891781".

This software update can be removed via "Add or Remove Programs" in Control Panel.

I have done this and have not, knock on wood, had any problems yet.  I did receive an dialog that said a couple other hotfixes and one application might be affected by uninstalling. I will post here if I have any issues that need to be passed on.  We recognize that uninstalling a security patch isn't the greatest solution, but it is, unfortunately, the only option we have right now.

UPDATE Feb 14: This update/hotfix seems to like to "install itself" without you realizing it. I've already had to uninstall it again today. If Qumana stops working again, go and check to see if KB891781 has snuck back into your system.
Believe me, this is driving us just as nuts as it is you.

If you have any questions please e-mail me at tris AT qumana.com.