Exploits that works for 4.2.0-9U

I have an O3DS FW 4.2.0-9U running Gateway. I want to install homebrew channel but none of the exploits that I tried worked. I did use browserhax on my N3DS and it worked perfectly, but it fails on O3DS. And I couldn[t find a savegame for O3DS for OOTHAX and Ninjax.
Any suggestions?