How to add command line in installsheild 2010 for silent install

Question

I’d like install sql 2008 express silently by InstallShield 2010 . I test this command in cmd prompt and it’s work.

SQLEXPRWT_x86_ENU.EXE /QS /IACCEPTSQLSERVERLICENSETERMS=True /INSTANCEID="SQL2008R2" 
/SAPWD="pass" /SECURITYMODE="SQL" /INSTANCENAME="SQL2008R2" /ACTION="Install" 
/FEATURES=SQLEngine,Replication,SSMS /ISSVCACCOUNT="NT AUTHORITY\NetworkService" 
/ASCOLLATION="Latin1_General_CI_AS" /SQLCOLLATION="Latin1_General_CI_AS" 
/ADDCURRENTUSERASSQLADMIN=True /SQLSVCACCOUNT="NT AUTHORITY\NETWORK SERVICE"

but when I add this command in installshield it is not work! why?

Question 1: I download sql express from Microsoft and add sql.exe in "Prerequisite Editor -> Application to Run", it's true?

Question 2: I add this command in second tier : "specify the command line for the application when the setup is running in silent mode:", it's correct?

Should I use installscript??