Formatting changes when opening spreadsheet on other computer

Situation:

1. There are 3 of us in our office.
2. We all use Window 10.
3. Two have Office 365 licences, I have a Office 2016 Small Business license.
4. Our master spreadsheets use specific column widths and line heights.

Problems:

1. One of the people with Office 365 has the following problem since March 19, 2019: his Excel 2016 does not seem to recognize all cells formatted as "Number, 2 decimals, negative numbers in parentheses and in red, with separator for thousand". These cells appear in the personalized model (# ##0,00_);[Red](# ##0,00).

2. Some column widths and line heights seem to change willy nilly from one computer to another. We wish them to remain as saved and not be modified every time spreadsheets are opened on a different computer.

I thank you for any insights you could bring on these very frustrating problems.