Everything has moved online now. Details to be filled.
https://administration-etrangers-en-france.interieur.gouv.fr/particuliers/#/
Standard steps are that you apply, get a receipt (recipisse) and wait for the card. Normally the receipt is valid for 3 months. During this time you are allowed to cross the French border with it (check). If you still haven’t received the card by then, the authorities will automatically extended your visa (Carlos can you fill in the details about your drama?) but it will only be valid in the Schengen area.
In the worst case do not worry and make your emergency trip outside of France, assuming it’s your home country! Plan to be there for a while but you will be able to get back home.
CNRS is a big organization and has the resources to sort out thing out. But it is like a big ship. Change of course takes time, effort and especially patience!!
For the case of titre de séjour passport talent, it is usually valid for the time you are hired. For instance in the case of phd students, it’s valid for 3 years.
Do not hesitate on keeping track of the paperwork. In my case, After waiting for the reply from the prefecture for about 3 weeks, they told me that my papers were lost and I had to send them again. In that case, the paperwork was not by the online service. At the end, I wait for almost 3 months for getting my titre de séjour.