I just discovered that there's a long-standing bug with newline symbols after a quotation mark being converted to text so that it shows up as "\n" in your rules.csv and in-game. Conversion was only supposed to happen for the script column, where each command must be on one line. A true fix is not possible at present, so I've decided to just disable conversion entirely.
That means, when you use a script command like AddText or SetTooltip and want to have multiple paragraphs, you'll have to remember to type "\n" instead of hitting enter. Thankfully, if you forget, the game gives you a helpful "unmatched quotes" error pointing to exactly where you messed up.
Additionally, you will need to fix any mistakenly converted newlines in your rules.csv yourself, which can be done in the Rules Tool (search for "\n" in the find dialog and exclude Scripts from the results).
Please download v2.1.1 in the OP.
Changelog:
Version 2.1.1
Bug Fixes:
- Fixed a save bug with newlines inside quotation marks.