The current version of this script DOES work. You just have to be careful, and know that it does NOT offer a 1-click distribution of ALL your flowers, hearts, etc. at once. It creates a list of your friends and you start clicking on them to send flowers. The difference is, you don't even have to move your mouse; just keep clicking in the same spot and the friends disappear as flowers are sent.
The WARNING comes when you click too fast - just like with crafting, if you click too fast and too often, you will lock up the game with the "streak of bad luck" error message. Delete temp files, clear cache, and log off/on to get through this problem, or just click on 20 at a time, go to the next world and do the same, and then come back for the next 20 and so on, until all the flowers have been sent. It STILL seems like a more efficient way of sending to your friends though.
Hopefully a future version will come up with a way to send them all with a single click, if that is possible. It's possible that 'streak of bad luck' glitch is what keeps us from sending all at one time, but we can always hope there is a way!