Restrict editing by users in a shared workbook

[Marcia]

Hi. I have prepared the attached workbook that will quickly tally the ballots in the national elections in May next year in our small town. I know it is still early but the filing of candidacy had ended last week and the names of the local candidates are already known. The workbook shall be shared among friends for our consumption (unofficial).
My problems are:
1. The sheets (15 sheets) contain lots of formulae but when the workbook is shared, the sheets must be unprotected so the other users could input their respective data in their assigned sheets. There is the risk of accidentally deleting the formulae or the names and positions of the candidates. Ideally, the users with whom the workbook was shared for data input must enter in the cells with white background only.
2. Because the sheets are unprotected, a user with editing authorization could open another sheet other than the sheet that which was assigned to him/her to update. I would like each user to view but not edit other sheets.
The only workaround that I could think of solving number 1 is to hide the Totals columns and all other columns filled with formulae. For number 2, I might just leave it to providence.
Any better solution would be very much appreciated.


Thank you.