[racket] about image operation

hello
there is little images(16x16) that cropped from other chipset
and I gether them and make an image which size is about 320 x 320

and I rotate it, but it is very very slow and blink alot

so I test basic polygon
it works perfectly, no delay, no blinking, even if when it grows big
the following code is tested
===================================================
#lang racket
(require 2htdp/universe)
(require 2htdp/image)
(define a (underlay (ellipse 10 60 "solid" "red")
              (ellipse 20 50 "solid" "black")
              (ellipse 30 40 "solid" "red")
              (ellipse 40 30 "solid" "black")
              (ellipse 50 20 "solid" "red")
              (ellipse 60 10 "solid" "black")))
(define (dr n)
  (overlay (scale  (/ n 10) (rotate (modulo (* n n) 360) a)) (square 300
"outline" "blue")))
(animate dr)
===================================================
and I also tested with original image(neither cropped nor gethered) which
size is about 200 x 200
it is very slow, and some times it doesn't working at all

1. is there anyway I can operate image faster as like other application?

and.. I still stuck at include image file when I create executable
I was told the way what I have to do (about 3 times)
but trivial error apear agian and again
could somebody please show me how to include image as relative path?
2. how to use bitmap and build-path function exactly for include image as
relative path?
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