Where can I find the setup file for tuner setups ?

I'm using the dm500hd official image , but it doesn't have satellites informations for those Asia/pacific sats (Australia)
I manually edited satellites.xml file to add a few, and saw those sats in the tuner setups.
But where is the file used to store those tuner setups?

No matter what lnb's LOF/hl settings are, there is always SNR 0% ! Is it possible that the tuner settings are not saved at all?
I'm using C band LNB D21B from ZINWELL with lo 5.15GHz, the dm500hd's LNB also has correct 13/18 v supply.

Any ideas? Thanks.