TransportLayer() not defined in Development System
Packages must exist on target system with correct transport layer assignment before any object assigned to it is synchronized on SyM.
If any Package in that TR to be synchronized doesnt exist yet:
create a new SyncReq and drag and drop not existing DEVCs (Packages) to this one and synchronize it.
Then change manually (SE80) the transport layers assigned to each package to the ones existing in that system.
Synchronize TR with objects you initially wanted to synchronize.