i am dont think 8 gb chips will work...
once my sis bought a 4 gb chip, and we waited 2 hours but it still didnt load.
the memory space is too big. i use a 2 gb one.
for downloading, i go to www.romulation.net . you need an account there, but making one won't take long. Type in ur search and just download the file.
ignore the file and go download 7-zip. Search it in google and click on the website given. you won't need to download 7-zip every time, but if u dont hav it yet then this is what you do.
after u get 7-zip, go back to the file you just got. Right-click it and click on 7-zip. Click on extract files. Ignore the bottom where it says u hav to put in a password. Just click OK. Then the file will download. A folder will appear on ur desktop. Click on the folder, and theres your game. Ignore the other stuff in the folder.
Insert your chip into the adapter and scroll down to "open folder to view files." Drag your game from the desktop into the new folder. Exit (click x) and take out ur chip. Insert it to the card and then into the DS. Turn your DS on, and instead of going to the DS menu, you will be automatically transported to the r4 menu. Click on the happy faces (the first option) and your game should be there.
If my explanation is a bit confusing, you can always search on youtube for a tutorial.
If you start ur game and it says: the save data could not be acessed, then go to r4ds.cn and install an upgraded version of the r4. Currently, that is 1.18 (like the r4 expert said).