I have been trying it out, very nice. Definitely an upgrade to the default.
I tried your control since I am having trouble with the default one on IE8+. It is giving me the same issue (the calendar shows then closes). I found a solution on the LDD forums (http://www-10.lotus.com/ldd/nd85forum.nsf/0/579744cf7198e21785257731006c9cea?OpenDocument), that I may have to try out. Wondering if you have had any issues in IE 8 as you worked on this.