Tutorial1Security example does't work

I’m trying to add a new custom security type and value function to opengamma, as described in http://docs.opengamma.com/display/DOC210/Adding+a+New+Asset+Class+Using+RawSecurity .

I’m getting
"WARN c.o.w.a.formatting.ResultsFormatter - Unexpected type for value. Value name: ‘Value’, expected type: java.lang.Double, actual type: java.lang.String, value:"
exception when trying to open corresponding view on analytics. Value column is empty.
Could someone help to fix this? How to add a new security properly?