Originally Posted by DisapprovingOwl
However, even with this version of ScummVM, I can't get the game to start off in Speech Only mode
I took a look at this. There's nothing wrong with the ScummVM version. It's in the boot script.
There is this variable initialized which tells ScummVM to turn subtitles on, thus overriding the scummvm.ini setting. It was probably a remainder from older SCUMM versions and no longer required. Just removed it, and the problem is fixed.