Scripted modifier for texture controlled animation

Hello! I am new to maxscript and will be very appreciate for advice.
I have interesting idea to make link between texture color on object parameters like position, rotation etc. The texture will be animated and it will create interesting objects movements. For doing that I have this procedure:

1. Create objects
2. Create one planar UVW map for all objects.
3. Volume select modifier with vertex selection level and Texture map for "select by".
4. Scripted modifier that will take Vertex Select Weight for the first vertex and set it to simple float variable.
5. Wire that variable to object parameter with wire or scripted controller.
6. Killer animation ready!))
The problem is with scripted modifier. I only make it work in one frame when button pushed, but it must work every frame like distance in tape helper.

Here the script:

plugin modifier vertexselectectionweight
name:"Vertex Weight Parameter"
classID:#(685315,452281)
version:1
(

parameters main rollout:Roll1
(
amount type:#float ui:spiner default:0
)

rollout Roll1 "vertexselectectionweight" width:162 height:300
(
button but1 "push" pos:[51,37] width:60 height:21 across:2
spinner spiner "Amount: " pos:[26,84] width:114 height:16 range:[0,10000,0] type:#float

on but1 pressed do
( spiner.value = meshop.getVSelectWeight $ 1)
)
)

I hope its understandable)) thanks!