Hi Gopi
I dont prefer to update down payments to asset master.. For that
1. Create a New Field Status group as a copy of G067 and assign Z067 to your Vendor related recon accounts... (Special GL A)
Supress the Asset No in this Field Status Group
2. Now when you create a down payment request in F-47, you will get an error F5 378...
3. Supress this error message in OBA5 - Enter Work area as F5 in OBA5 and supress the message no 378 to W
With this Down payments wont post to Asset.. This is one of my favorite solutions... May be I should file a patent 
Br, Ajay M