I must say that the prices you offer sound incredibly fair, and so does the offer to get custom tracks as a bonus on top of a 75USD purchase - so fair, in fact, that this immediatly sparks my interest.

However, the problem here is that your licensing page is just way too vague. Access to the full license text presumably requires me to email you, and even if it isn't, that feels kind of fishy to me. Why not put it out in the open? Your target is game developers, who want to do the right thing and be safe in what they're adding to their game, and an unclear license or one hidden from us is not the way to go. Right now, it seems that there's some very unpleasant terms waiting for me in there, which is why you'd rather hide them from me.

Don't get me wrong - I'm not yet fully convinced this isn't just an oversight. In fact, I very much hope it is. However, this is an oversight that you NEED to correct.
Let us know which license you're using - heck, stick to one of the CC-licenses if you want - and especially let us know what happens should our game turn out to be the next Minecraft overnight sleeper hit, to suddenly hit that magical 40k/a (is "P" standing for pounds here? Or is it some other mysterious unit? What if it's Peso?) - am I just screwed then?

Again, I like what the sound of what you're offering, but as it's stand, your licensing is so vague that I could not in good conscience recommend you guys to anyone, which just sucks if your licensing is fair and really just not yet quite decided on what happens after those 40k (but, well, that MUST be decided and known in advance to you selling something UNDER that license)

So, fix that issue, put up a license that's fair to both parties, and that is complete before I buy (and/or email you), and I'll come back. Until then, I'd recommend everyone to proceed with caution.