That's because the .\hlsl\* files are taking precedence and they don't have the *.png entry.
First thing to do is wipe the old HLSL area from mame.ini, then run mame.exe -cc to create the new u6 version sub section.
The aperture.png shadow_mask_texture line from mame.ini is not written to the .\hlsl\*.ini files. Each game run gets a new *.ini w/ that same problem. I worked around it by using a single named hlsl.ini file to prevent individual ones from being created (put in mame.ini): hlslini hlsl
However if you run a new game that hasn't been run it will wipe the shadow_mask_texture line in the .\hlsl\*.ini file, so you need to be aware of that and add the aperture.png back in until it's fixed.
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Re: Anyone not seeing the shadow mask?
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Try replacing your hlsl folder with this
