I'd had the exact same flash card for over 4 years now. To write games onto the cart you have to insert the cart into the supplied writer. Then using the cart's manager, you can write the roms, burn saves (.sav), upload saves to computer, etc.
I've uploaded the original manager here:
http://www.sendspace.com/file/f9x6az
A little warning, on the bottom of the window the size of your cart and the memory left will be displayed. But you can only see half of it. This is just an XP glitch, which isn't important but i overcome that issue simply by quickly dragging the window down to the taskbar and holding the mouse button (if that makes sense).
To install the manager, extract the .zip file and plug in the writer. when the windows installer appears it will ask for the driver. Click advance and point to the extracted xgflash manager drivers.
All gba roms use the extension .sav. Different roms have different types of saves such as eeprom, flash, etc. But the manager will still accept them. If a game's save doesn't work with the xgflash, (eg. final fantasy tactics advance) simply use gbata (http://www.gbadat.altervista.org/gbadat/tools/gbata7a-en.zip) and 'SRAM'Â patch the rom.
Hope this helps
is there a website where it tells it which game needs to be patched?? or is it only a few games like final fantasy tactics needs to be patched?