Hi Jun ,
The word 'Extension' is a bit confusing when I refer to a custom application.
I think I must say " changing a existing custom application ".
Yes I would like to sync and change the application.
The question is how to sync first time.
If I follow the below procedure.
1. I download the existing custom BSP application.
2. Import in my local Eclipse.
3. Make Changes
After that I have 2 options to sync .
1) Upload to SAP and overwrite (as suggested by Viswa)
2) Sync using Team provider.
Are you suggesting me the 2nd option ?
Thank you