Used the default settings of l1j-en for opcodes and it worked with lineage15.com's Windows one.
Got a pull from the SDL-based Intel Mac client attempt of Doors-Software.com's Thomas Epperson (uglyoldbob). It's a C++ based project that uses a makefile. His git repo is based on Windows and has Linux and Mac branches. I fixed a memory leak that was crashing the Mac Intel version. Maybe it wasn't crashing for him due to using ARC? Haven't found out yet, but I wasted many hours trying to get that thing into XCode and just could not get it to go. That's its whole own essay.
I finally got the Mac version built just using make. Had to swap out Opcodes.java and ClientThread.java back to what they are on his tikal_antharas_native branch of l1j-en. I can't stop thinking that it would make more sense to use the other opcodes that we know work. I also learned that his client is very early-stage without working sprites or many other things. What he's done so far is incredible but there is clearly much more work to be done. It would be very interesting of course but I'm wondering how much it would be worth to do.