Hmm, yeah, something might just be wrong in this save. If somebody knows the event ID for Caroline's 2 heart event, maybe with save-editing it could be removed and then watch the event again to try and trigger the recipe, but I don't know the event ID for that one, sorry. Perhaps someone else can help with that if you want to try it.
My only other thought was... I also just got this event, and I did get the letter and crafting recipe, no problem. But what I did notice is that the recipe doesn't seem to appear in the same place in the crafting menu as it used to for me. As in, I think before 1.5 it used to be on the first page of crafting recipes, right next to crafting a grass starter, but now it's down on the 2nd or 3rd page of crafting recipes wayyy down by... argh I don't remember what it's next to anymore. Maybe the new fiber seeds recipe, though that doesn't help you if you don't have that recipe yet.
I guess what I'm suggesting is just go through your crafting recipes very carefully and check all pages, because it might not be in the location where you expect.
