The instructions you are using are for old components that have been upgraded. The TX and RX buffer can't be less than 4. The program I sent you works with the 4 size buffer. Check the PDF file in the new program it doesn't say to set it to 1.
Always use the latest code and information. Your example was written in 2012 that is a long time ago and the PSOC components have been updated many times since that date.