Well, not sure what is going on. Until today, I had never tried to get the WOT payware locos to work in anything above 2006. So, I took one (DE-SD75M BNSF Auto# H-II (Fuel) Hood Lights,<kuid2:86105:6460:2>) and exported it and all dependencies (including the gatekeeper) to CDP and then imported into TS-2010. Everything committed without errors (only 2 warnings) and works fine in 2010. So, these questions.
Are you exporting 2004 or 2006 content to TS-2012?
What is the specific loco (or one of them) you are trying to take from 2004/06 to 2012?
It could be that the WOT locos work in 2010 but do not work in 2012. Could have something to do with old 2004 content you are trying to bring into 2012. I don't know. I don't understand why, if these locos work in 2004/06, do do not have their dependencies in 2004/06. I don't have any unknown kuids in any of my WOT locos.