pls write following code in text file in save with .bat extension.
1)path of QV.exe /r path of applicatin
you can put multiple application in single text file.
in your case pls put interface application in only one batch file which you want to execute ones.
batch1: ETL Application
batch2 : ETL Application
batch3 :- ETL Application + pls put interface application in this .bat File
then schedule the application with help of window schedule.
if you still require any help pls reply me.