I record my customized sound using on-phone recording (pressing *77). If I try to listen to it bye dialing *99 there it is..I can listen to it and after saving it with a name I can see it under /usr/share/asterisk/sounds/custom/.
However, if I select it to be played prior to join the queue (Queue>Join Announcement) it won't be played as other built-in recordings do.
I don't know where the problem is. I changed permissions to be 777 for /sounds given the fact that before FreePBX was launching a message like "unable to save" after trying to save the recording.