please check this script

[bazz]

my first post on this awesome forum!!

i am very new to Avisynth and find it mind blowing.
Ive spent hours this week searching for a good script to denoise and sharpen DVD and 720p MKV files using alongside MeGUI

i used this script on VOB files yesterday with great success

LoadPlugin("C:\Program Files (x86)\MeGUI\tools\dgindex\DGDecode.dll")
DGDecode_mpeg2source("E:\megui\VTS_01_1.d2v", info=3)
LoadPlugin("C:\Program Files (x86)\MeGUI\tools\avisynth_plugin\ColorMatrix.dll")
ColorMatrix(hints=true, threads=0)
#deinterlace
crop( 0, 10, 0, -8)

Spline36Resize(624,336) # Spline36 (Neutral)

a= last
b=a.degrainmedian(limitY=3, limitUV=5,mode=0).VagueDenoiser(threshold=1.2, method=1, nsteps=6, chromaT=0.8)
SeeSaw(a,b, NRlimit=3, NRlimit2=4, Sstr=1.5, Slimit=5, Spower=5, Sdamplo=6, Szp=16)
Undot()
GradFunkMirror()
Grainfactory3(1,1,1)

only ive tried to use the same script on 5 different MKV 720p files and after a few seconds Avisynth crashes
The usual error is
" unable to load directshowsource.dll "

i read on google someone fixed this error by uninstalling MeGUI from program files and running it from elsewhere but that did not work.
Its definetly the script because ive got MeGUI running now with no filters added:confused:

can anyone suggest a work around please.

edit, ive noticed its when i go back and add this to the script

a= last
b=a.degrainmedian(limitY=3, limitUV=5,mode=0).VagueDenoiser(threshold=1.2, method=1, nsteps=6, chromaT=0.8)
SeeSaw(a,b, NRlimit=3, NRlimit2=4, Sstr=1.5, Slimit=5, Spower=5, Sdamplo=6, Szp=16)
Undot()