Fixed my IE issues…
By adding a DOCTYPE entry to my index page I got the toolbox to position itself correctly.
And by changing the DIVs I was using for the link items in the data set and member lists to SPANs, I was able to remove the forced inline display option I had had to add to make things display on a single line. Seems that DIVs inside anchor (A) tags is not W3C valid anyway. Live and learn!