You can create or even override colours using the tag. We recommend defining all of your colours in a tag at the top of your panel:
<abs contexttype="opengear">
<meta>
<color id="color1" name="Custom Colour 1" value="#B41B63"/>
<color id="color2" name="Custom Colour 2" value="#00FFFF"/>
</meta>
<label height="83" left="62" name="I'm using colour 1!" style="txt-align:center;bg#color1;" top="63" width="283"/>
<label height="83" left="366" name="I'm using colour 2!" style="txt-align:center;bg#color2;" top="62" width="283"/>
</abs>#DashBoard