Transdem 2D UTM tiles intstead of 1km basemaps

[cauman]

I came up with the bright idea of using transdem 2D UTM tiles instead of ordinary 1km basemap tiles in a existing none transdem trainz map. Utm tiles being able to be produced at a much higher resalution.
I tried this idea by placing previously produced UTM tiles by hand in an empty 16 board trainz map. This worked vey well,the tiles being able to be manovered one by one to produce a seamless basemap.
Only one disadvantage. It is only possible to move any one tile in an X-Y dirction in increments of 40 meters.

Anyway of getting round this problem? And why 40 meters?

[geophil]

40 meters is the Greatest common divisor (GCD) of the 1000m UTM grid and the 720m Baseboard grid.