Oy people having problems with my contrib! Super Q to the rescue :)

Well I've taken a look at the code for the weight, and I see the problem is with an undeclared variable that is being used as part of the where clause in the attrib search. However, I didn't create the total weight portion of the code so I'm trying to get some help from the author on what the value should be for that variable.

In the mean time, I added the tare check to the totalweight code so now it at least adds that part correctly. I used a snippet from the way the checkout shipping class does it and it seems to work fine.

I'll get this fixed and release it with a new version as soon as I hear back about the attrib stuff.