Show/hide rows based on drop down cell using named ranges

hi

I've found various threads showing how to hide/unhide rows based on a value in a cell and built a form based on the code I have found. The form has three uses and shows hides sections (rows) of the form dependant on the option selected in a cell (B1) This works fine but I now have a requirement for users of this form to add addtional rows into some of the sections but as they do this sections further down the form move down so subsequent sections then have different row numbers to that in the VB. I thought that I could use named ranges instead of row numbers but as soon as I put in the named range I get runtime 13 mismatch error?

Please help.

The attached sample has a drop down in cell B1 for options A, B or C and dependant on this selection, groups of rows are hidden.
Each grouping of rows already has a named ranges (Range1 to Range5) but how do I use these in the VB?

Many thanks

Stuart