Hello vkamp,

You can try this code :

   <style type="text/css">

        .testHeight{ height : 50px !important;}

    </style>

<igtbl:UltraGridColumn Key="Item" BaseColumnName="Item" Type="DropDownList">

                     <ValueList>

                       <Style CssClass="testHeight" >

                         </Style>

                           <ValueListItems>

                           <igtbl:ValueListItem  DisplayText="Text1"/>

                            <igtbl:ValueListItem  DisplayText="Text2"/>

                            <igtbl:ValueListItem  DisplayText="Text3"/>

                           </ValueListItems>

                      </ValueList>

                  </igtbl:UltraGridColumn>

I was able to apply custom rules for the dropdown only if I define a css class outside of the grid and reference it like in the code above.

Hope that helps.