Phantom texture
I tried to reproduce what you described as a problem, but I didn't see anything unexpected. Perhaps I don't know what you mean by "marquee" and what you're actually doing.
1. When I first started, I only had the first 2 versions of the PBR Grass mixed 64 texture installed. I had not yet downloaded the latest version of the texture (the seasonal version).
2. In TRS19, I created a new Route and bulk-replaced its preset ground texture (PBR Grass 8 - Seasonal) with PBR Grass Mixed 64 <kuid2:473136:104964:1>. The recursive dependency list of the Route confirmed that <kuid2:473136:104964:1> was being used, but it still listed the preset texture as a dependency despite it being replaced on the map. This apparently has been normal for Trainz for a very long time. In the Route itself however, the whole baseboard was covered in PBR Grass Mixed 64 <kuid2:473136:104964:1>, and it was the
only texture that came up when using the "Get texture" tool and in Surveyor's texture palette. In other words, Trainz was only showing and only using the highest version of the texture available to it and ignoring the earlier version <kuid:473136:104964> even though it was also installed and available.
3. After downloading and installing the
latest available version of the texture, PBR Grass Mixed 64 seasonal <kuid2:473136:104964:2>,
but before using it on the Route, the dependencies list showed that the Route was still using <kuid2:473136:104964:1>, but was also aware that it was now an obsolete version (because the higher version now was now installed).
4. Next, I simply opened the Route and sampled the ground texture. It was now automatically using only PBR Grass Mixed 64 seasonal <kuid2:473136:104964:2>. There was no sign of the previous version anywhere on the Route baseboard itself (using the Get textures tool), or even in the Surveyor textures palette. The dependencies list of the Route also only showed the latest version of the texture.
So, no "phantom" obsolete version of PBR Grass mixed 64 was detectable in the Route or in Surveyor's palette. Note that I had not done any database re-builds. This all just happened automatically.
5. My final step was to delete PBR Grass Mixed 64 seasonal <kuid2:473136:104964:2> from CM to see what happens. It again left PBR Grass Mixed 64 <kuid2:473136:104964:1> as the highest installed version of the texture. I checked the dependencies list
both before and after I had opened the Route. It had automatically returned to the previous state where it was again using <kuid2:473136:104964:1> but was aware that the DLS had a newer version available (i.e. all the way back to Step 2). So its process of finding and using the highest version of a texture was quite reliable, whether you're adding higher versions or removing them.
This all seems perfectly reasonable to me. I could not reproduce any "phantom" instances of the obsolete texture. I admit that at this stage, I don't know what you were doing with the Marquee or why you think an obsolete version of the texture was somehow interfering.
I can only suggest that you delete any obsolete versions of the texture from CM, leaving only the seasonal version installed, then do an Extended Database Repair to clear up any scrambled references. Then open your Route and use the "Delete Missing Assets" and save it. After that, I can't see how it could possibly still find an obsolete version of the texture, let alone use it. Even if the obsolete texture is "built-in" and locked against deletion, it still should be a non-issue if a higher version is installed.
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