I did some tests with that chip and also using a rs485 chip to test. You talked about rs232 and a direction (TX_ENABLE) and when I look at the code I think it's RS485, but that is not an issue.
I also discovered that indeed the chip will not startup when using HSERIN and the RX pin of the uart is high.
I put a 10K resistor from the RX pin of the picchip to ground and now the program is starting up normaly.
I hope it will help you.