I programmed some electroanalytical methods for EGG 263 potentiostat which is similar to 273A (CV with many cycles and impedance spectroscopy for 263 with 5110 EGG lock-in amplifier). I think it is extremely difficult to build complex program which will be able to access all potentiostat functions. So you have to program your own program which will access only few functions depending on type of your task.
The good teaching material how to program EGG instruments is driver for EGG 5110 on zone.ni.com, more complex one is on www.signalrecovery.com or you can contact me via email Martin.Krondak@vscht.cz