Decimals

In the lessons we are taught about the decimal point being "virgule", e.g. Two point five = deux virgule cinq. However, my understanding is that virgule is actually a comma, and the reason it is used like this is that French standard notation is to use a comma for a decimal separator as opposed to a point (period or fullstop), like many other nations do.

If however you are reading a document, and mention a section headed 5.10, you would actually say cinq point dix, ne c'est pas? (While the comma, "virgule" is reserved as a decimal separator only). Does this change in other French speaking countries, where the decimal separator is a point (period or fullstop)? Do people then use point instead of virgule even for decimal numbers?

Furthermore:

1) does one read a decimal no 5,46 as cinq virgule quatre six or cinq virgule quarante-six? and
2) I assume one would read a heading 5.12 as cinq point douze . . ?

I just need to be sure my understanding of this is correct, before I end up in a French boardroom one day,. confusing clients.