[Steins Gate] libnpengine crashing when starting new game

[spycrab]

Here is the console output:

void NSBInterpreter::CallFunction_(NSBContext*, const string&): Failed to call function Patch
steins-gate: (...)/steins-gate/libnpengine/src/Variable.cpp:106: std::string Variable::ToString(): Assertion `IsString()' failed.
Aborted (core dumped)

I'm using the JAST version of the game and the --exe 1 option