- A single file can't have two same events.
- Wrong control is used. it should be the animation control from ctl_gen.mdx
- 1001 refers to a dialog control which doesn't exist. should be 2.

Here's the correct init event:
Code:
on *:dialog:anim1:init:0:{ 
  mdxinit 
  mdx SetControlMDX $dname 2 animation > C:\Program Files\MDXStudio\ctl_gen.mdx
  did -a anim1 2 open $scriptdir $+ test.avi 
  did -a anim1 2 play
}

Hope that helped smirk

(Note, for debugging, it's recommended to use //echo -a $dll() instead of just //dll, so if there's an error you'll see the information returned.)