Traps for you players ... If you install on a 64 bit machine you will get ORA-12154 errors on attempting to connect to your Oracle database. This evidently has something to do with the 32 bit Oracle client connector not liking the path the application is executing from (i.e. C:\Program Files (x86)\Devart\OraDeveloper Studio\oradev.exe) If you execute the program from a command prompt using:
C:\PROGRA~2\Devart\ORADEV~1\oradev.exe
the problem is resolved ...