Texture and JAM editing for objects in GP2 tracks

[samsepi0l]

I am curious - are there best practices for JAM sizes when making textures for buildings? I notice that if I try and use the 'horizontal repeat' and 'vertical repeat' numbers in the gp2 track editing tools they don't look right many times if the JAM is not a size that is a power of 2. For example, if I want it to tile nicely on the side of a building it needs to be 32, 64, 128 wide. Also I notice there is a "nonstandard jam width" flag that you can check- but it gives really strange results sometimes. Like I notice sometimes that part of a wrong JAM will appear in the game, but it does not show up this way in the object editor?

[rremedio]

I know tiling textures with sizes that are powers of 2 is usually the prefered approach for many engines, even modern ones