I have found that when importing into a model from a spreadsheet, less is more. The more columns you are importing, the more likely it is that something will fail. My spreadsheet has 2 columns. Column 1 is the parent, which is the table index, identified as <table name>.<index name> and column 2 is the table column, identified as <table name>.<table column>.
When importing, the column parent is identified as parent, and the column is identified as type column, with sub-type of table column from the drop down.
This will associate table columns with the index. I let the default sort value of ascending stay unless I need to change it in the model.