[PerfectHT]

Yellow kinda stands out, and means to me the file has not been properly scraped into the library. Ensure your movies are in separate folders of the same name (with date) and there is only one video in the folder and named Naming video files/Movies (wiki). T! does recognize 4K but doesn't see the UHD designation. You can make a smart playlist or node to tease out specific UHD files based on some naming extension or path.

Once a video has been scanned and assigned a resolution (hence colour cover) it can be changed manually (method below) or removed from the source, the system cleaned up to eliminate the file in the library and then re-scraped. 

To change the cover from SD to HD would be taken from the .nfo whihc you have exported to separate files to the movie folder.

e.g.

Code:

<video>
                <codec>xvid</codec>
                <aspect>1.330000</aspect>
                <width>512</width>
                <height>384</height>
                <durationinseconds>5190</durationinseconds>
                <stereomode></stereomode>
 </video>

Changing the resolution and then a local rescan will bring the colour cover associated with the resolution. Of course the .nfo is formed on scrape and the appropriate res is assigned at that time. At present only SD, HD, sets and 4K are delineated in T! unmodified covers , but if you augment the covers broadcast and pal resolutions are available.

In general it sounds like you have a sloppy library, with a non-standard naming convention. Once you have cleaned up the nomenclature, I suggest clearing your sources, system clean-up and then re-scan should establish your library in a more satisfactory manner.

I have AEON MQ8 on my another player and testing it now.  Aeon has no problem to recognize different formats.  It recognize all UHD movies without a problem.  The same about DVD including two HD DVD, however it used blue case.  (I don't blame them, who still use HD DVD.)  It shown DVD and 1080p for HD DVD, so it is correct.  Still testing but it looks good.