I actually done it a long time ago using nHTMLn but now DCX is around i would do it with DCX. nHTMLn has issues with 6.2 anyways.
Check out the /xdock function in the DCX documentation. You will have to learn about Cell Layout Algorithm.
/xdid -j dcx 4 alert('Hello')
allows you to execute javascript on a webcontrol

step one: make one html file (You will only need one).
step two: create a dialog table called html for instance.
step three: on join open a generic dialog name. i.e dialog -m $+($cid,$chan,.html) html
step four: ON *:dialog:*.html:init:0: {
-call xdock on the appropiate hwnd.
-browse to the html file from step one
-Apply a CLA scheme so it resizes appropiatly.
step 4:On some event call xdid -j on the webcontrol on the corresponding tablename to manipulate the DOM from the html file you browsed to in the init.

You gotta really want it wink


$maybe