Ticket #4810: step by step again, but end of work today

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@38137 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
NPE fix

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@38138 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e