Well...after a lot of try, i finally managed how to open the .sav (Battery Saves, NO SAVESTATES!)
I search in google, and all dingoo related sites, and dind't found a solution for this, so i make my own
Some GBA games, require cable-link for finish them (e.g Pokemon games), and dingoo GBA Emulator of Native OS don't have cable-link option, so we need to open or savegames in some PC emulator with cable-link emulator like VisualBoy Advance (VBA). In this tutorial i will not explain how to use cable link (vba-link in this case), you will find a lot of tutorials in internet about that.VBA 1.7.2 + VBA-Link: http://www.megaupload.com/?d=T8NQL0EH
Lets take Pokemon - Red Fire as example. First of all, pokemon games use 128k saves (no supported by the dingoo gba emulator) so we need to patch the rom with GBA Tool Advance
). This is not necesary for all games
Download - Unzip - Run gbata.exe and apply SRAM Patch
If we don't chaged the output directory, we will have a new file named "output-YOUR ROM NAME.gba", in my case "output-Pokemon - Rojo Fuego.gba". Delete original .gba file, and rename the output file without the string "output-"
Now we can use the battery saves in the game (.sav files). IMPORTANT: If already have a savestate (.st0, .st1, etc) or battery save (.sav) in your dingoo, u will have to delete them all. Savegames generated before apply SRAM patch, will not work.
Now we can play in our dingoo the patched rom, and use the game save option, that will generate a new .sav file.
Now we copy the .sav generated by the dingoo emulator and the patched rom into the VBA folder.
Run VBA, go to Options -> Emulator -> Save Type and select "SRAM"
Open the rom, and go to File-> Import -> Battery File, select the .sav file. This will reset the VBA and the game will start again. After the game opening the game will load our save (it will be say there is an error, and will load the "last saved game", but is ok, its works) and rdy! we have our dingoo save in VBA working. IMPORTANT: We must do all steps in order, after save the game, we must close the dingoo emulator. If u don't close the emulator, and try to open the save, the game save will be deleted (i don't know why..). So is recommended have a backup of your progress using the savestates (.ST0, .ST1, etc..)
Now with the .SAV working in the VBA, we can do whatever we want, for example, use cable link (vba-link)
After do "whatever we want", we can save the game in the VBA (using the game save, no savestates), and this will generate a new file of extension .sg1, .sg2, etc.. rename him to .SAV, go to your dingoo, delete all .SAV, .ST0, .ST1, etc of that rom and copy the new .SAV file into that folder. When u open the rom, the game will load the save after the game opening.
My english is not very good, if u don't understand something, just ask!