Add instanceof check before casting to Node to Element - in the case of some XML files with whitespace between nodes, this can cause a ClassCastException:

com.sun.org.apache.xerces.internal.dom.DeferredTextImpl cannot be cast to org.w3c.dom.Element in OpenLyricsObject

The DeferredTextImpl is just whitespace and so should be ignored, not cause the library to fall over - the instanceof check ensures this.