Given time I think I could figure this out with VBA but if someone can provide concept code that would be great.
I have attached a spreadsheet - it has a "Main" page with 3 columns of data (Category, Attribute & Property). The idea is to use the main sheet to specify data to other sheets (new or existing).
Each sheet represents a category (in other words each category gets its own sheet). The data in the sheet is UNIQUE combinations of Attribute and Property.
Listbox 1 is used to select or create a new sheet (Category)
Listbox 2 & 3 are used as data on the new sheet (concatenate Attribute & Property)
In my demo file I have manually generated a sheet called Category1. I hope to have a userform that is able to manually add to the category if the unique combination does not exist for that category.
I envisage single selection on Category, single selection on Attribute, and multiple selection on Property (combinations that already exist in the category would be indented and not selectable).
Pressing OK would:
Create / Access a sheet with the name of the selected category
Add the unique combinations of concatenate(Attribute & ":" & Property) to the category.