Build Your Own SLA/SLS

Hi there. Recently, I had created .png mask file by using UV-sensor, NURBS-surface and Z-buffer. And got a few good prints with it.
But now, for some reason, I am no longer able to use it. I enabled mask in CW interface, checked Default_SLA.machine, but all I got was just normal white layers without any mask. I checked mask file location, trying to change it, but no luck.
I was trying 1.0.0.36 and 1.0.0.75, but no difference. Don't know what to do next.

The mask file is here:

Did you remember to hit the "apply changes" button? I know I've forgotten this on occasion...

It can also be hard to tell if it's working sometimes so I made a mask file with a black stripe in it so I could easily tell if it was applying the mask.

Yeah, I remember. And I had tried to load really dark mask, but no changes, I got clear white layers.
Maybe, something is wrong with my OS, I'll try another computer.