File won't open In Lightroom Classic

I have just updated Photo AI to 3.3.3… Lightroom Classic will not open the files that I have edited in Photo AI and saved back to LRC. They show as gray in LRC.

Topaz Photo AI [v3.3.3.] on [MacOS 15.1.1]

This is more complicated than I initially thought. Here is the description that I have sent to Topaz Support:

A .tif created by PhotoAI and saved back to Lightroom Classic will not open in LRC.

Here is a detailed description: A .nef (Nikon Z8) captured with the monochrome picture control displays in colour in LRC. I use the Basic panel to convert it to B&W. Then I use Photo/Edit In/Edit in Topaz Photo AI to send it to Photo AI. I apply sharpening and noise reduction, then click on Export to Adobe LrC. LrC displays a grey box with the error message “The file appears to be unsupported or damaged”.

I can open the same .tif in Photoshop but PS gives this message: “The embedded ICC profile cannot be used because the ICC profile is invalid. Ignoring the profile.”

I do not experience the same problem when following the same steps with a .nef that I have not converted to B&W.

Topaz support helped me with this:
“Photo AI does not support a RAW File shot in monochrome to be sent with the non-RAW file path. You will need to use the RAW path, from File > Plug-in Extras > Process with Topaz Photo AI.”

Topaz support is great.