**Update** I have noticed that these cmd files are missing from recent ssdt builds, to enable logging see Kevin's comment:
http://blogs.msdn.com/b/ssdt/archive/2014/07/15/sql-server-data-tools-ju…
**/update I was helping someone get a deployment filter working in SSDT recently and the issue was that they had configured the publish profile to include filter but when they did a publish or generate script, an error occurred with no more detail than “Contributor initialization error.":
Being stuck at what to do next I had a poke around and found the SsdtTrace.