I was able to solve this problem using "pointer-events". Checked on Mac (Safari, Chrome and Firefox).
All magic is here:
.overmap {
position: absolute;
top: 100px;
left: 50px;
pointer-events: none;
}
.container .full {
background-color: #ffffff;
pointer-events: fill;
}
Please check the demo (central column is passing event to a map): http://jsfiddle.net/giftedev/qu2Lduwp/ and let me if any questions.