Not sure if you found a solution. Ran into this issue myself and found the solution. Make sure that your CSS says 'proxima-nova-condensed' instead of 'proxima nova condensed' as in the example below because CSS does not recognize the font otherwise.
h4 {
font-family: 'proxima-nova-condensed';
font-size: 28px;
color: #202020;
font-weight: 500;
line-height: 1.4em;
}