I have a tune that I've been working on and I have several tracks (some will be replaced) laid down. I want to send a copy to a keyboard player so that he can work up his part. But when I try to attach a file to an email, all the files in Reaper come up individually instead of the entire tune coming up as one file. How to make the project one file, minus a final mix? If it's a wav. file, can he play it without having Reaper?