My encode result is a green messed up video

[Eamon]

I have checked the karaoke script in the program I use to make it (Aegisub), and it shows the correct preview fine when I switch the program's plugin to VSFilterMod.

have you checked the output of your script? (For example using the Avisynth Preview?)

Cu Selur

When I try Avisynth Preview, the window pops up and shows a preview. But it's on the first frame and not on the frame where the karaoke subs should show up. So I scroll through. When I reach around the point the karaoke subs should show up, the window instantly closes - as if crashing?