re: Excel tips: How to populate cells after locking other cells

Not exactly clear.

To answer the title question, it's pretty easy with a macro. If they are savvy and want to cheat, they can. You could just build a macro that they press to "lock-in" their picks. This would unlock the workbook structure, and hide/unhide worksheets, then lock everything back.

The problem would be when they saved the file after picking, the next guy would see the picks last guy made.

You could possibly also build it in an access database. This would have similar coding, but eliminate the opening/saving issue. Their picks would be recorded to a master list that only showed after selecting/locking all their picks.

Another way to address it is to fix the "time-consuming" part. Come up with a format that you send out, and have them return with a specific filename, ie "Pick Em - John Doe". Once all spreadsheets are returned and unmodified (locking cells and data validation), just have a simple macro that "builds" your master spreadsheet, labeling by filename.