the issue is caused by the filter: alpha(opacity=100); setting in the styles/dmxpopup.css on the dmxWindow selector
.dmxWindow
{
position: absolute;
visibility: hidden;
top: 0;
left: 0;
height: auto;
width: auto;
background-color: #fff;
overflow: hidden;
border-top: 1px solid #dedede;
border-left: 1px solid #ccc;
border-right: 1px solid #ccc;
border-bottom: 1px solid #ccc;
z-index: 50000;
-moz-opacity: 1;
opacity: 1;
filter: alpha(opacity=100);
-moz-box-sizing: border-box;
box-sizing: border-box;
}
Remove the opacity setting to fix the error.
the simple way to hide the info balloon is to enable driving directions in the pro maps wizard, but leave the starting address blank.