You need

.midcol {
    overflow: visible;
}

That won't suffice by itself. You have overflow: hidden; applied to .link ( the link container). This stops the links from running underneath the floated sidebar, which is fine. Problem is that it will also prevent the upvote text from 'escaping' the bounds of the container.

To have it work for links and comments, and with RES, you need to replace

.thing .upmod:focus::after {
    content: "";
    font-size: 12px;
    margin-left: 1px;
    position: relative;
    color: ##FF4500c;
    bottom: 18px;
    opacity: 0.0;
    -webkit-animation-name: exAn;
    -webkit-animation-duration: 2.0s;
    -webkit-animation-timing-function: ease-out;
    -webkit-animation-iteration-count: 1;
    animation-name: exAn;
    animation-duration: 2.0s;
    animation-timing-function: ease-out;
    animation-iteration-count: 1;
    animation-play-state: running;

}

@-webkit-keyframes exAn {
    0% {color: #FF8C69}
    8% {bottom: 23px; opacity: 1.0}
    15% {bottom: 28px;}
    30% {color: #FF0000}
    50% {color: red; bottom: 33px;}
    60% {color: #FF4500}
    100% {bottom: 38px; opacity: 0.0}
}

@keyframes exAn {
    0% {color: #FF8C69}
    8% {bottom: 23px; opacity: 1.0}
    15% {bottom: 28px;}
    30% {color: #FF0000}
    50% {color: red; bottom: 33px;}
    60% {color: #FF4500}
    100% {bottom: 38px; opacity: 0.0}
}

with

.thing .upmod:focus:after {
    content: '';
    font-size: 12px;
    position: absolute;
    color: #ff4500;
    bottom: 40px;
    opacity: 0;
    -webkit-animation: exAn 2s ease-out;
    animation: exAn 2s ease-out;
}
@-webkit-keyframes exAn {
    0% { color: #FF8C69; }
    8% { bottom: 43px; opacity: 1; }
    15% { bottom: 48px; }
    30% { color: #f00; }
    50% { color: #f00; bottom: 53px; }
    60% { color: #ff4500; }
    100% { bottom: 48px; opacity: 0; }
}
@keyframes exAn {
    0% { color: #FF8C69; }
    8% { bottom: 43px; opacity: 1; }
    15% { bottom: 48px; }
    30% { color: #f00; }
    50% { color: #f00; bottom: 53px; }
    60% { color: #ff4500; }
    100% { bottom: 48px; opacity: 0; }
}

Replace

.link {
    overflow: hidden;
    margin: 0px;

with

.link {
    margin: 0 310px 0 0;

then add

.midcol {
    overflow: visible;
    position: relative;
}
.res-commentBoxes .commentarea .comment {
    overflow: visible!important
}
.res-commentBoxes .nestedlisting {
    margin-right: 310px;
}