I'm with Filux there, really think it takes a button. You just don't click on text, since you don't expect text to be functional. This is not done anywhere else in the game (with the exception of text input boxes) , nor is this a common concept on any other common UI. So it both deviates from handling anywhere else in the game and thus users just won't become aware of it, so 'm afraid the code you crafted there just won't be usable to anyone else but you and the few people reading this thread.
I'm stressing this so much because I think our UI quality is already not that great and introducing new elements which deviate just makes it worse. I would definitely like to see the feature implemented (with proper GUI), though, and appreciate the work you spent on it.
Regarding ???ShowNextHint???, whenever you add a reference to a new language key to the code you also need to add it to the corresponding English language file. In this case this should be the main language file. Transifex pulls updates from language files every European night, but Transifex project admins (currently softcoder, titi, I) can also use the 'tx' (transifex-client) utility to push files to Transifex.