NoMethodError in ReportsController#subreport

Hi,

I'm testing your Reservation Tool. When i want to create a report for a Equipment Model, i got this Error:

66 67 68 69 70 71 | EquipmentModel.where(category_id: params[:id]).collect(&:id)          else            sanitize_sql(params[:id])          end      # also NOT a SQL-injection -- id_symbol is built by ClassFromString,
-- | --


do you have a solution for that?
thanks!