Thank you! DataGridXL is awesome as well. None of what we're doing would be possible without data grid libraries.
And yes, good catch on the drag after a single click, we're tracking and plan to fix :)
Interestingly, I've found that newer database-like spreadsheet apps like notion or airtable favor the single click to drag and reorder columns behavior. But for a more analytical tools where multi-column selection is more relevant, click and dragging a column should simply multi-select columns.