Is the addition of some new textures important to you? If you are using 2004 then Trainz Objectz can allow you to delete or interchange textures.
Modify your Trainzoptions file by adding -showkuids. Then, in Surveyor, you can select 'Get Texture', left click on a texture you can do without, and the KUID will be shown in the bottom right hand corner of the screen. TrainzObjects can then be used to delete that texture from the map, and if my supposition is right you can then add another texture.
There is something to remember that Auran have said is true and others profess to have proved wrong. Auran stated way back that at any given point on the route, even where ground textures have been overwritten completely, up to five of the overwritten textures still exist. Despite the 'proof', I believe Auran are correct.
Try this. Make a new map, paint a ground texture over a small area, record the kuid, COMPLETELY overpaint the first texture then do this about seven time more, each time recording the KUID and completely covering the previous texture. Save the map. Go to \world\custom\maps and open the config.txt of the map, you will find that the kuid-list will contain just the last five textures you used. Thus you have a map that ostensibly uses just one texture, but Trainz knows better.
You may not have used 254 textures but you may have experimented with many that you then covered with different ones. Those unused textures are still there to haunt you.
A little bit tof Trainz trivia to amuse you.
Cheers
Narrowgauge
