When sending a SQL statement from Foglight Peformance Analysis to SQL Re-Write, all alternatives (plus the original) are showing a plan cost of 0.
RESOLUTION 1:
Go to the 'Connection' menu | Open Connection Manager | check the 'Privileges' column for the connection currently being used. If it says 'Limited User' then review the missing privileges: (see Additional Info)
RESOLUTION 2:
Change the connection being used to that of a Power User (has all privileges required for running Optimizer)