MSP430F169 BSL NAK (0xA0)
I recommend modifying your serial driver to add at least a 50 ms delay between transmitted bytes - longer is fine. These things do not have a real UART so they can be quite finicky.

Your format should be 1 stop bit, even parity.

The particular commands you show in your examples are password protected. Have you prefaced them with a 32x 0FFh RX password cmd?