Multipass shader from shadertoy

I am recreating a multipass shader from Shadertoy and something goes wrong in the process of passing the outputs from jit.gl.slab to jit.gl.texture. in my tests I notice how the alpha channels, which are used as data channels instead of actual alpha, don't seem to go through the multiplass process properly. I tried to switch off the filter option in the textures but it didn't improve the situation. I think there should some other default preference that I need to change but I can't seem to find it. I am attaching a zip file with a maxpatch and two jxs