Membership Plugin Invite Codes don't seem to display properly

Using Membership plugin with invite codes and BP default theme (and original membership form.) The invite code text is top right but the input field is at the bottom (see screenshot.)

Changing line 99 in membership/membershipincludes/addons/simple.invitecodes.php from
<div class="form-element"> to <div class="register-section" id="blog-details-section"> seems to have fixed the problem, but is it just me? Did I miss something?

Also, the invite code field doesn't show up if I choose the pop-up registration form. If I submit a new user registration using the pop-up form, it goes to a blank form. Is there a way to get invite codes working with membership pop-up registration form? Thanks for your help!