You are correct. I've not added code to work around all the garbage collection bugs in IE. I'll take a look at this next time I update the XLoadTree.
There seems to be a memory leak in the XLoadTree code.
If I start the Performance Monitor and look at the private bytes for Internet Explorer. Then there is an increase when I (at the XLoadTree demo) unfold a folder. Good, but when I reload the page, then there are more private bytes used than before. And this senario continues