Possible to use PNG with Transparency for watermark?

[grafical]

I'm trying to batch process a folder of 24-bit TIF files (no transparency), applying a watermark image on top, and saving them to JPG.
The watermark image is a 24-bit PNG image with transparency. The opacity / transparency is already built-in.. in other words, I'm applying it at 100% opacity in xnView because I've already reduced the opacity to 50% in Photoshop when I created it.

When I batch process the TIF files, they are converted to JPG properly, and the watermark PNG is applied, but the PNG is not transparent.. In the areas where the PNG file is transparent, the JPG is solid white.

I see under the Options button there is:
PNG \ Compose image with Transparency
PNG \ Compose image with alpha (32bits)
and then:
Transformations \ Watermark \ Don't use alpha of picture

I've tried every combination of the above 3 settings and the alpha areas from the PNG are always solid white when it is placed over the TIF and saved as JPG. Is there some other way to do this?

[xnview]

Only with 32bits PNG

[grafical]

That's what I don't understand.. Thumbsplus shows the file as "24-bit+alpha", and it shows me the transparency properly..
If I open the PNG in Photoshop, it shows transparency properly with a checkered background.
In xnView, if I right-click the PNG and select Properties, it says 32 bit per plane, but the preview does *not* show transparency, just solid white.

[xnview]

could you send me it?

[grafical]

I sent it by private msg. Thanks for checking it out.