Here's another take on making a quad mesh out of this object. (first one was http://www.makehumancommunity.org/clothes/topboots_one.html) Here I splitted all the tris and ngons by hand. It looks more decent, but the mesh is still super weird and gives nan's in mhx2. I've also made an attempt on UV map (the boot is black, the inside is white, the sole is dark brown). Adding an actual texture might be problematic though because of some faces being all stretched and what not. Upd 11.12.2015: Uploaded an experimental texture file in "bump texture" slot. It is a diffuse texture still. Upd 15.12.2015: An updated version of the texture in "bump texture" slot.
CC0 - Creative Commons Zero