NJK - Thanks. For your site, it looks like the CSS of the template is clashing with the module changes for version 9.x.
Can you try adding this to your theme for SCLogin? It adds some standard background and display styles. The modal is there on your site, but not shown properly through styles.
div#login-modal.modal.in {
display: block !important;
background-color: #FFF;
top: 5%;
position: fixed;
left: 50%;
z-index: 1050;
width: 80%;
margin-left: -40%;
height: fit-content;
}
We changed the way we're rendering the modal now to use built-in Joomla rendering. It may be adding more classes to the modal popup that weren't there before, hence causing the new template style wonkiness.
Let us know if this works for you.
-Melissa