If it has weight, then that should mean that you have either killed Lucien Lachance or have completed 'Honor Thy Mother' in the DB questline.
Here's a link with more info. http://www.uesp.net/wiki/Oblivion:Blade_of_Woe
Note the weight. It should be either 0, 1 or 4 and is pretty well explained. No idea why it would weigh 10. The UOP is not the problem. I don't use the other mods you have.