Unfortunately RailClone does not currently have a UVW offset parameter, though it has been requested before and it is on our wishlist for a possible future release. You can see another thread about this here
In the meantime the best way currently is to use the material operator and either create multi-sub object materials, or use it in conjunction
with CG Source's Multi Texture map (free) or VizParks Crossmap (paid) to save loading bitmaps one at a time.
Alternatively, since the geometry for a floor is typically fairly light and to avoid a large number of bitmaps, you could duplicate the source geometry multiple times, then either apply a UVW map modifier that encompasses them all, so they each take a different part of the texture; or shift the offsets manually using UVW Xform modifiers (or a UVW randomising script such as this one
). These are then brought in as segments and variation is created using a Randomise operator.
If the situation changes regarding the progress of the UVW offset feature then we'll keep the forum updated.
I hope that helps,