Yes. It worked for me with 2 accounts. I got both up and running.
I didn't try very hard to break the launch process. I downloaded and installed the game. I ran it outside of InnerSpace once in order to ensure the game config files were created (
edit: Oh and I set the game to run in Windowed mode, not fullscreen, not Windowed Fullscreen).
I setup InnerSpace to launch the NCLauncher.exe, using the parameters noted.
I did note that the NCLauncher.exe actually loads up NCLauncherR.exe. I also noted that the game loads the 64bit version rather than the 32bit, and there is no option to force the correct one unless you bypass the launcher and load up the aion.bin directly (this has different params which you can find on the Aion forums and the
ISBoxer wiki, although I think the Aion forums params were slightly different, maybe.
I tried logging into the same account, which it would let me, but it would kick the other one out of the game once I hit Play (actually I get System Error 20, and then it bombs out)
I tried the wrong password.
I did create a virtual file for the NCLauncher.ini. Not that this is necessary.
I did launch my game from the InnerSpace right click menu, selected ISBoxer Character Sets, and then my character set.
I did not try launching from ISBoxer or desktop shortcuts.
I did not use the games at the top of the InnerSpace right click menu (because these don't run the ISBoxer config).
I did not manage to replicate your issue, which sounds more like a failure to authenticate, and the launcher spitting it back out. That might be network related. If you are trying to do proxy/vpn stuff, that could be a problem. Same with any packet inspection. Sometimes Antivirus can do weird stuff too. Windows App Compatibility settings can also do weird things.
Perhaps a
diagnostic would be in order.