I would like to address your both questions.
1- If we see the expression in Windows Title window it is concatenating the field names (airline, origin etc) with KPIS Per. So whenever the current field will be there the Title Will Display as "KPI's per Airline". If Origin is selected then it will display "KPI's per Origin"
2- It is displaying in red because there is something incorrect in your expression syntax. In this case i believe those filed are not present in your database. Qlikview shows red line (Syntax error) if your are wrong somewhere.
To make this happen just load the filed in your script and then use the expression. The strairght table will display the title.
I hope this is clear to you now