Sorry, I didnt go into much detail and after some research in this forum there apears to be a problem/bug in Zbrush with SUV function, i.e you loose all UV smoothing if you move down to a lower Sub D level. The steps are as follows.
1: Create a mesh and make Uvs in Modo.
2: I import the mesh, store morph target.
3: Enable SUV and start to Sub D tehe msh adding form and detail.
4: This is the step where I have to go back down to level 1, to generate a displacment, because I have moved back down the sub D level, the SUVs fail to smooth the Uvs for any colour texture work.
The Uvs are as they would apear at level one smoothing, even athough the mesh is at level 6 Sub d.