Conditional Formatting - Formula Problem?

you went into problems with rounding values. (not your fault - just known excel problem).
The numbers in excel are stored as double precision (some 15 digits shall be acurate)

see rows 14 and 15 if you use not 2 decimal digits but more:

HTML Code: 

of course your rule for conditional formatting returns red, because value in column B is different from E

The cure (one of possible) - change the CF rule formula to:

=AND(ABS(E2-B2)>0.00001,E2<>"")