It's been running for 3 days on my 4.2U, NeoGamma R8 Beta 12, Rev 14, with main.dol patched default setting on NeoGamma R8 Beta 12, it loads from within HBC channel and using the channel concept posted a few pages back, with no errors or any issues.
Rev14 sorry forgot to include that in my post
also I'll be testing to see if the channel concept posted works for launching the NSMB via DvD as well
Edit: just installed the NeoGamma R8 beta 12 channel posted by concept and it boots NSMB from the channel with no problem
NSMB boots just fine from dvd on my modded wii
4.2U system menu
main.dol patched NSMB
NeoGamma R8 Beta 12
no problems been playing it since yesterday. Burned two copies one for me and one for my neighbor both same setup and both play fine.