I recently downloaded a horizontal numbered hotbutton. Here is a portion of the xml file, perhaps the LAbel portion is the part which denotes a number.
.......
<Pieces>HB_SpellGem5</Pieces>
<Pieces>HB_SpellGem6</Pieces>
<Pieces>HB_SpellGem7</Pieces>
<Pieces>HB_SpellGem8</Pieces>
<Pieces>HB_SpellGem9</Pieces>
<Pieces>HB_SpellGem10</Pieces>
<Pieces>HB_Label_1</Pieces>
<Pieces>HB_Label_2</Pieces>
<Pieces>HB_Label_3</Pieces>
<Pieces>HB_Label_4</Pieces>
<Pieces>HB_Label_5</Pieces>
<Pieces>HB_Label_6</Pieces>
<Pieces>HB_Label_7</Pieces>
<Pieces>HB_Label_8</Pieces>
<Pieces>HB_Label_9</Pieces>
<Pieces>HB_Label_10</Pieces> .........
Here is the horizontal hotkeys if you want to check it out.
-Lauren