Yes and no. The text display is sort of limit, and while ordinary speech can probably overrun the box without much issue, it caused problems when there's a choice. If there are enough lines of text that it overflows vertically, the game seems to get confused about what it's supposed to display firstly, and it breaks the selections if the player tries to interact with lower options.
I didn't actually watch what happened in the code, but my suspicion is that an incorrect option value is returned. Under normal circumstance, the scripts will indicate that the player must make a choice, from X number of options represented by however many text strings. Then the options are numbered, and when the player makes a selection it actually runs through the remainder of the script looking for the appropriately numbered block of code. Each block is terminated by the same set of values that indicates the end of any event script. So either it reaches the end of the entire script without finding a block of code to run, or it accidentally runs an incorrect block of code that appears to correspond to the bad option number from the input. Either way, you'll get to the end of the script fragment without having run the correct code, and either the game has nowhere to go subsequently, due to event flags and the like not getting set, or control flags are left set that render other script un-runnable, or any of dozens of different possibilities.
For Two River, they added an extra line break to give emphasis to the hero saying, "always," I guess. That option takes three lines of the four that are allowed. The second option had two lines just due to its length. Daring to press down caused the game to get lost, and I'm not sure you could even safely pick the first option at that point. In Gregminster, they had three options and sort of arbitrarily decided to put line breaks in two of them. More for looks maybe, because neither was in much danger of overrunning the margins of the box. Since the last option there is required to continue from that point, you're doomed if you get to that screen. In both cases, reformatting so the text all fits in one display fixes the issue.