Don't know, but feel free to use my code. It only needs two images (or it can just work with one) and seems to work pretty darn well. The only thing is the width of the image needs to be divisible by 10 or else there will be alignment problems:
//Start Variables
$puts(ratewidth,90)
$puts(xpos,0)
$puts(ypos,2)
$puts(image,$getpvar(image_dir)'\rating-stars_small.png')
$puts(image_unfilled,$getpvar(image_dir)'\rating-stars_small (unfilled).png')
$puts(unfilled_alpha,100)
$puts(normal_alpha,170)
$puts(mouseover_alpha,255)
//End Variables
$drawrect(,,,,brushcolor-SYSCOL-15 pencolor-null)
$puts(rateheight,$div($get(ratewidth),5))
$puts(halfstar,$div($get(ratewidth),10))
$puts(rating,$if(%rating%,%rating%,0))
$imageabs2($get(ratewidth),$get(rateheight),,,,,$get(xpos),$get(ypos),$get(image_unfilled),alpha-$get(unfilled_alpha))
$ifgreater($get(rating),0,$imageabs2($get(ratewidth),$get(rateheight),,,$mul($get(halfstar),$get(rating)),,$get(xpos),$get(ypos),$get(image),alpha-$get(normal_alpha)),)
$button2(0,0,0,0,$get(xpos),$get(rateheight),,,TAG:SET:RATING:,)
$puts(rate,1) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,2) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,3) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,4) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,5) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,6) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,7) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,8) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,9) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
$puts(rate,10) $button2($get(xpos),$get(ypos),$mul($get(halfstar),$sub($get(rate),1)),0,$mul($get(halfstar),$get(rate)),$get(rateheight),'','$imageabs2('$get(ratewidth)','$get(rateheight)',$mul($get(halfstar),$sub(10,$get(rate))),,,,,,'$get(image)',alpha-'$get(mouseover_alpha)')',TAG:SET:Rating:$get(rate),TOOLTIP:"Rate:$get(rate)")
Here's the two images I use for my rating panel.