Image sequence as textures not working in V-Ray 6

I am using V-Ray 6 in Rhino 8 and I am trying to do something very simple: add an image as a color texture.

For some reason about half the images I try work just fine, the other half are just shown as grey!? I have tried different file formats, etc. but I just don’t get it.

An image that does not work:

An image that works fine:

I just don’t understand what even could be the problem. UV is the same between images, there is no transparency or anything like that. Just a simple image in either .jpg, .png or .tif. You would think loading an image is solved in 2023. (12.7 MB)

Has anyone else experienced this? I’ll attach the 2 images in a .zip.

Ok, so I narrowed it down to when V-Ray thinks there is an image sequence. As soon as you turn off sequence you can see the image.

But so how do I render a texture with an image sequence?

Here is a sequence of images to try: (6.6 MB)