Well it seems to me, you mentioned yourself *donations*, now I don't know the case but accepting donations and forcing users to pay for the game as opposed to contributing financially to it of free will, is VERY different.
Aside from that, if he has a legal copy of the software, I'm pretty sure he would have full right to those RTP resources (to use them freely in projects whether in or out of the original application), it really doesn't make any difference, unless the original author has explicitily stated otherwise (and let's not forget half of the materials, especially music is not exactly *original*).