are you sure, you've follow the steps exactly? try do it slowly...
While the game is loading, you need to hold down the Button where the codes are saved in until the game starts..usually about 2-3 seconds (5.12ff) after the pie is filled.
Yes, I've done it exactly, to the letter. Several times from the beginning.
It doesn't matter whether I hold a button or not, or whether I load the dipstar.ds.gba or not. Whenever I try to load the patched rom, it fills the pie and then sits there. It doesn't go to two blank screens or anything, the G6 menu is still there with the green pie filled. I've left it for over ten minutes and it never goes away. I have tried it by pressing A to select the rom and then immediately holding the L button, and held it for over three minutes. It just sits at the pie.
The m3dip.exe patching is clearly messing up the rom. The rom works perfectly before patching. I've re-patched the clean rom with the G6 software and then dropping it onto m3dip.exe again as well, no difference. Perhaps I need to get a different version of DipStar.
I tried checking m3adaptor.com and the only thing I can find on the entire site is the dipstar.ds.gba file with a readme.txt (they're packed into the file 'DipStar NDS Cheat Code.rar') There is no full DipStar download package that I can find on the site. I have the 5.12ff version from the link in your last post, but that's not working for me.