1. Your averaging formula field has the braces for the REF fields typed. You can't do that. They must be created via Insert|Cross-Reference for the bookmarks concerned, or via Ctrl-F9.
2. You can delete the CPC1 bookmark and field associated with it and simply code your averaging formula field as:
{=({REF TS2}+{REF SS2}+{REF SRSA2}+{REF OD15}+{REF Clinical2})/{IF{REF Clinical2}= 0 4 5} \# 0}
3. Your document contains a mix of formfields and content controls. These were not designed to work together in the same document and shouldn't be used that way; inconsistent document behaviour can result. Stick to one or the other.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]