Setting IMS resource height (resource is shown or page is resized) fails when page-header or page-footer element can't be found.

Module.js function imscp_get_htmlelement_size first line returns false if element is missing.

Maybe test for false set default value if element is missing:

var val = YAHOO.util.Dom.getStyle(el, prop); // val is false if el is missing
if(val === false){
val = "0px";
}