Help:VE34
From TrainzOnline
Alias mesh meshname.im not found in latest version (<kuid2:##:##:#>) of dependency <kuid:##:##>
This signifies that a mesh container specification which includes a mesh-asset reference to a mesh which does not exist in the relevant mesh library.
Given this container:
coupler { mesh-asset <kuid:1234:5678> mesh screwlink.im }
the message would signify that screwlink.im is not present in the latest installed version of <kuid:1234:5678>