Do I have to take into account the accent maks in the concepts to watch?
It is not necessary that you write the accent marks, because the platform does not distinguish between words with or without accent marks. This is to avoid the effect of transcription errors. Although it is more stylish to write with accent marks!
On the other hand, you should note that the symbols (e.g. $, #, etc) are taken literally. Thus, it is not the same to specify "R&D" than "R+D". If you are interested in both, you have to declare both in the vocabulary.