Design a Tree in a blank Report

I'm creating a report like a Tree structure.

Area1          Total Modifications in Area1
  Type1         Total Modifications in Type1 in area1
   Sub Type1    Total Modifications in Sub Type1 in Type1 in area1
   Sub Type2    Total Modifications in Sub Type2 in Type1 in area1

  Type2         Total Modifications in Type2 in area1
   Sub Typex    Total Modifications in Sub Typex in Type2 in area1
   Sub Typex2    Total Modifications in Sub Typex2 in Type2 in area1

Area2
  Type1         Total Modifications in Type1 in area2
   Sub Type1    Total Modifications in Sub Type1 in Type1 in area2
   Sub Type2    Total Modifications in Sub Type2 in Type1 in area2

  Type2         Total Modifications in Type2 in area2
   Sub Typex    Total Modifications in Sub Typex in Type2 in area2
   Sub Typex2    Total Modifications in Sub Typex2 in Type2 in area2

I used the Report Wizard, created a Tabular report, did the grouping, and choose the Table Layout as Stepped and enabled the Drilldown and subtotal and it is works perfectly. When clicked on Area1, it shows the Type1 and Type2, and when clicked on Type shows the Sub type..

Now the problem is i have all the complex SQL code for this in a Stored Procedure.

When using Stored Procedure, Report Wizard cannot be used. So, How do i achieve similar Stepped Tabular report with drilldown feature when i create a blank report with Stored Procedure in Dataset

I used Table control and added two groups for Area and Type. I made the Area as Parent for Type and tried Hide and visibility Toggle option but i got error
"Toggle items must be text boxes that share the same scope as the hidden item or are in a scope that contains the hidden item, and cannot be contained within the current report item unless current grouping scope has a Parent."

Is this the way to do it or am i missing somthing in this

Any help with steps appreciated.

Thanks.