You can try either automatic and manual, or hybrid approach.As your protein is so small, I think you can just try PINE. If your C-HSQC is constant time, you will get very accurate results with PINE.3. Just type ep in the NMRFAM-Sparky and add your experiments, and click submit. To bootstrap your current assignments to enhance the results, enable Use pre-assignment.

1. Use of PINE-SPARKY.2 plugin for automated assignment

http://www.nmrfam.wisc.edu/pine-sparky2.htm

2. PINE-SPARKY extensions for validation

http://pine.nmrfam.wisc.edu/PINE-SPARKY/sparky_extensions.html

Let me know if you need further help.

Best,

Woonghee