When using merge tags it is possible to set a default in the case that the data to be pulled in is not available (For instance a missing first/last name). The default can be changed based on the specific merge tag. To do this, insert the desired merge tag which will appear as "|^GEN_firstName / DEFAULT=^|".
To change the default, place your desired text between the "=" equals sign and the "^" caret.
Here are some examples using the first name merge tag:
Hello, |^GEN_firstName / DEFAULT=Valued Customer^|
Hello, |^GEN_firstName / DEFAULT=Example 2^|
Hello, |^GEN_firstName / DEFAULT=Loyal Customer^|
Hello, |^GEN_firstName / DEFAULT=Name not found^|