I've been steering clear of Fallout 4 [official site] chat because I fear I've already ruined too much of its magic and mystery by having to read so much about it for work, so this one passed me by at first: a nasty bug seems to be crashing the game for everyone in a certain area at times. Spoilers will follow, but right here I'll be plain: be warned that you'll likely crash if you wander into Monsignor Plaza (having not played yet, that means nothing to me). If you have business there, you may be able to get around it.
Folks on the Fallout 4 forums have been feeling around the limits of the bug, noting that Monsignor crashing only starts after a certain point in the story (spoilers, obvs).
A few quests will send you towards Monsignor Plaza, though. If you want to finish 'em and not wait for Bethesda to fix the problem with a patch, the thread also collates workarounds for most. They tend to involve using console commands to magically warp around the world, or to advance quests. Not quite as satisfying as going in and doing it yourself, I suppose, but it's either that or wait.
One imagines this'll be a reasonably high priority for fixing, but Bethesda haven't said when that might come.
If you're bugged by things which aren't bugs, just oversights, do check out this tweaks for things like the game's field of view. Heck, you might get something out of these important things the game doesn't explain too.