Try using this emulator called "DeSmuME" (search on google, or something).
After I used the patch, I couldn't even get past the shrink ray scene, on No$GBA.
Then, when I heard about DeSmuME, it started to work fine, except for the occasional freeze.
The usual signs of freezing were no icons on the bottom screen, messed up overworld sprites, and black grounds/walls.
Hope this helps you!