BEFORE STARTING ANY TYPE OF HACKING/EDITING TO YOUR OBJECT(S), BE SURE TO MAKE A COPY AND STORE IN A SAFE PLACE. That way, if you mess something up or something doesn't work right, you still have the unchanged object.
This tutorial came about from an issue I was having with a custom endtable. Anything placed on the table was sinking down into it:
After much help from Peter Gould, via Simblesse Oblige, I figured out how to fix this error. Then fantastic Olena Dub (Olena's Clutter Factory) asked me for help on a similar issue. This tutorial was born... Click on a picture to enlarge.
Open your object's XML file and find the SLOT resources section (Fig-1). It should be one of the very first things. You can use any XML reader or editor, or you can just open the file with Notepad.
Locate your desired height on the height table (Fig-2; courtesy Simblesse Oblige).
Edit the "height" value to your desired height (Fig-3). I had to go from an endtable height to a desk height to get the objects to sit correctly on my pedestal table.
That's it! Save your changes and exit. Re-import you object in T'mog, and test in your game.