My cell formulas have gotten fairly complex and I was wondering if
there is a way to perhaps format sections of the formula differently to
make it easier to read. For example, maybe bold everything before the
"+" and underline or something after.

My gut feeling is the answer is no, but it never hurts to ask.

(((PHYD0181-((ASMP01 WNRL_)*HYD0181))*(ASMP01 PHMYD_))*(ASMP01
SNHMAD_)) +

((PHAD0181-((ASMP01 WNRL_)*HAD0181))*(ASMP01 PHMAD_))*(ASMP01 SNHMAD_)

Related to this, is it possible to add CR and LF characters to a cell
formula? It would help if I could break the formulas at the "+" sign,
for example.

Any help is much appreciated.