I'm trying to build a structure with 80/20 aluminum extrusions using SW weldments.  I've created the two profiles I need to use, and started building the structure, but have run into some problems.  Refer to the attached file.  I've included my profiles.

1. The trim/extend tool doesn't give me the result I want:

a. I trimmed the body Horizontal1 using the body Vertical1 as the trimming body which seemed to work, except that Horizontal1 extended into the centre of the Vertical1 even when I select 'simple cut between bodies'.

b. When I then try to trim Horizontal1 using Vertical2 it says the operation fails due to geometric condition.

2. I can't get the weldment cut list to update!  Even before trying the trim/extends...

Where did I go wrong?

I'm using SW2009 SP4.0.