MAIO for R4iDSN/R4iGold was a lame work around that I imagined up one day and Mantis decided to pack up into an actual package. The only reason why there was a difference in those versions versus the regular R4 was because the R4icn team were jerks and only allowed their _ds_menu.dat to be the initial booting firmware.
Anyways, I can give some instructions...hopefully they make sense to you.
1) Grab a copy of your woodr4 kernel (official probably) and extract it some place where you can make sense of everything I'm going to tell you (in other words, some place clean).
2) Make a duplicate of the _ds_menu.dat, globalsettings.ini, and lastsave.ini and name them WoodR4.nds, alwaysautoboot.ini, and redirect.ini respectively.
3) Edit the alwaysautoboot.ini to have autorunWithLastRom=1
4) Edit the redirect.ini to have lastLoaded = fat0:/Moonshl2.nds
5) Open the _ds_menu.dat in a hex editor.
6) Change all instances of "globalsettings.ini" and "lastsave.ini" to their respective renamed .ini
7) Put moonshl2 in as you normally would (and maybe have the moonshl2.nds in the root of your microSD like bullet 4 would have you believe).
8) Get inilink from the mshl2tools...
http://leafmoon.users.sourceforge.net/xenonnds/files/ and set it up.
9) Supposedly it should work now unless I forgot something.
-edit-
Oh...and that is pretty much the method to using any of the alternative menus on the R4icn flashcarts...because they are asshats who don't read and follow my egotistical wants.