Badly drawn images ftw :P... Still, it should be clear what both things are.. A .... and a ...... Just combine those two words and you got yourself the answer.
46 is another alphabet riddle. How many letters does the alphabet have? How does this apply to the substitution you are talking about and the numbers that are shown on the riddle screen?
For 42, write down the 'important sentence', exactly as it is posed in the article. The sentence is one of the two clues in riddle 42. The other is the image of the yellow ball. Whats this yellow ball? How does this link to the sentence? If you are still stuck, I could give you a revealing hint, just give me a nudge if you want it.
Level 46 is really all about this tiny substitution and applying this to the title... You have to see it, obviously, but you are making it harder than it is. I'll tro to reproduce the odd jump you can make btw, thanks for telling.
About level 15, think of an item that, when you breathe in it, a warning sound will emerge. The answer has nothing to do with Lotr, its just used a lot in Lotr...
@Profdepipo, if you didn't have this problem, then its ok :).
@Pynkk: Notice the arrow and at what its pointing, you clearly need that. Can you think of a way to make letters out of a colour?
Glad you liked it, Profdepipo, but I think something went wrong. At level 42 you could go to the end of the riddle, whilst you weren't supposed to. I fixed it now, but I think you already got there... Well, if you like, you can still do the other 8 riddles, but the last 10 are really hard.
On another note, hints are added, so enjoy.
 "Riddle X"){kind=icon}