Looks like you got your problem solved, but I want to add a couple things.
- This issue used to frustrate me a little bit until I realized that, since the slope table is associated with the alignment, we have to select the alignment for the button to activate and them to appear in profile view
- The "_EditAlignmentAsSpreadsheet" macro includestabs for the slope tables and can be an easier way to get data into it depending on your workflow.