Backslash escaping not working (on Windows?)

A report from @Horatio-Blackwood, via HipChat.

```
VAR char_name = "Joe"

* \ {char_name}: This is the choice
The end.
-> DONE
```

(We use the backslash in this situation, somewhat awkwardly, to escape the following space and allow "Joe" to appear in the choice text, rather than turning `{char_name}` into a conditional for the choice.)

This appears to work:
- On Mac
- On Windows via CLI

But not:
- On Windows, via Unity integration (for @Horatio-Blackwood). It prints the backslash itself.

Need to reproduce, and debug.