AS the title says, the generated CSS from pinegrow leaves off the ending semi-colon ( ; ) from the last definition in the class. So, for example:
.imageCaption {
margin: 0;
padding: 5px;
width: 200px;
}
ends up being
.imageCaption {
margin: 0;
padding: 5px;
width: 200px
}
This happens consistently even if you go back and edit the class again with the visual editor.