You know, I find it amazing that after 19 pages of questions, the original author hasn't bother telling us how to solve the of the postbits. And he didn't even bother adding a fix in his instructions. Someone should tell the mods that this hack is NOT supported.
And just to add something constructive, here is a thread in vBulletin.com which explains how to add a column without doing crazy things with the table widths etc.
http://www.vbulletin.com/forum/showthread.php?t=101599
It's mentioned before, somewhere in those 19 pages I read.