Error Parsing /page.xhtml: Error Traced[line: 42] The entity "nbsp" was referenced, but not declared
Facelets is a XML based view technology. XML has only five predefined entities. The is not among them. It works only when used in plain HTML or in legacy JSP (note: it doesn't work in JSPX as that's also XML based!).
To fix this, you either need to declare the entity yourself in the doctype of the very XHTML file containing the entity,
<!DOCTYPE html [
<!ENTITY nbsp " ">
]>
or, better, use the (hexa)decimal notation instead:
  or  
In an average IDE it should be trivial to perform a "find and replace in all files" and replace every occurrence of by  .
Try using &#160;. for more information on entities you can refer following url HTML ISO-8859-1 Reference
For me the following doctype enables :
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">