This is the simplest MSP430 circuit I could find, from an example stepper motor controller project:
A simple RC filter between Vcc/Vss and a filter cap on the external crystal. I will use header pins for my external power connection. For external power I will use a lab power supply and alligator clips. External power requirements will be 3.3V at 500mA. Update: The sole purpose of this board is to show signs of life, it will never be used anywhere but the lab bench. The power jumper added an extra bit of complexity with no benefit and should be removed. Power will always come from the JTAG probe.