See

http://buildlogs.mongodb.org/MCI_windows-64-2k8/builds/111407/test/tool_0/dumprestore7.js
http://buildlogs.mongodb.org/MCI_windows-64-2k8/builds/111407/test/tool_0/exportimport4.js
http://buildlogs.mongodb.org/MCI_windows-64-2k8/builds/111407/test/tool_0/exportimport5.js

The spaces in the value passed to the --query argument to the tools are breaking command-line parsing.

This is probably because of an escaping issue on windows where

"{""ts"":{""$gt"":{""$timestamp"" : {""t"":1412692831,""i"":21 }}}}"

becomes

"{\"ts:{$gt:{$timestamp", ":", "{t:1412692831,i:21", "}}}}

when it is read in by golang's flag parsing library.