Logon Box - User / Pass - Unique Actions Per User.

I have a workbook that is used to track overtime hours worked through the year. I've received some help from users on this forum, and others, to create the necessary macros and formulas to allow a supervisor to make use of the form; however, the workbook is also used to track those that wish to volunteer to work overtime each weekend. The sheet has a list of names for the employees on each shift, then a column to allow a "Y" to be placed under the date - designating them as a volunteer for any overtime available. I've found this spreadsheet (attached - from this site) that will allow individual users to access the workbook and have unique passwords for each. I don't completely understand how it works, but I feel it may be a start to getting what I want.

Essentially, once the user selects their name and inputs their password, I'd like the workbook to be opened and then allow them to only manipulate the row associated with their name. That row will change from week to week, so specific numbers will not be able to be used, but their name will be the same as the name used in the logon.

I feel like I'm asking for a lot here, so just some initial guidance on whether this type of thing is possible would be an acceptable answer.