I dont know where some sounds came from (or cant remember), i got them from an other player (I think about to disable it for the custom gamemodes of plus, because there are the score counter is working diffrent in these)...
About the download problem... I know this, but i dont know exactly where it some from, it have something to do with the dll, but I normally disabled the part what have to do with it and I get the crashes only at bigger music files >1MB and sometimes without JJM sometimes too.

(As Info, If I not answer all things It's not that I'm not reading them, all what you say here is readed and I try to add you wish or fix the bug)