Alpha blending different video planes OR sync vidPlane movement + dif texture

Hello, thanks in advance for any help.
In the process of building a mixer in jitter, having some trouble with one of the steps.

I have 4 video planes, 6 videos, 2 static images.
The two static images are alpha PNG files. I'm including samples. The first is a PNG with alpha removed, and the second is a mask for the first.
Here's an example video of it so far (using clips we probably all recognize from archive.org)http://vimeo.com/7258228

Genera layout
Vid1->slab->Blend -->VideoPlane layer1 (background)
Vid2->slab--^

Static image1-->texture+alpha-->VideoPlane layer2 (

Vid3->slab->blend-->chromakey-->VideoPlane layer 3 (foreground
Vid4->slab--^

static image2-->texture--> ????

Style wise, the first layer is creating a chaotic, audio-synched visual generally. The static images need to by synchronised in terms of their movement, so what I imagined was just a larger-than-viewable plane with a series of textures mapped over top using these techniques: https://cycling74.com/forums/index.php?t=msg&goto=173823&rid=0&S=5c439d72bedf777947143089ede620a5&SQ=b508f6324371e753e5fe6f78357c91c8&

Problem: I need to have the two static images synched position wise, but I need image2 to be removing the masked parts of vid3/4's textures. In the video example, I managed to do this using blends on the same video plane, but the programs changed a lot since then and so has what I see as my goals.
I would be happy to just use the blends to remove it on the same plane, but I'm not sure how to then make synchronous the movements of the 2nd image layer and the blend image layer (which at that point would be a texture).

Anyway, any help would be appreciated. I put together a really quick example patch to illustrate what I generally mean, but yeah, the full patch is still a bit too big.... If I don't make any sense, do let me know, I'll try harder!