From experience with the beta and memory, your wife (and you) will be able to choose which version to play. Either yours with a ton of DLC or hers with none. You should both be able to use the version with all DLC, but not at the same time.
It's been a while since we tested this though so things might have changed, including my memory...
Sure. You have to solve it from inside out:
The huge coincidental part is that ඞ lies at a position that can be reached by a cumulative sum of integers between 0 and a given integer. From there on it's only a question of finding a way to feed that integer into chr(sum(range(x)))