Hello Daniel,
the number of polygons is quite small for such big amount of used images. Are you simplifying your models? If so, what is your process?
What unwrap settings are you using? And again, number of textures seems to be too low for such amount of the images.
I checked the texture process, and at about 70% step the texturing should be finished and after that the re-coloring should start. Can you check your texture settings and try to turn off the Recolor model after texturing option?
Also, maybe it is not necessary to use full scaled images in your case. Then you can try to check this tip: https://www.youtube.com/watch?v=5B6Vd5CWTtQ ?
Also, where are your images saved?