I made a lot of changes.
Your relationships were defined incorrectly so I fixed them. I also fixed the PK names and table names. I cleaned up the tables and removed the unnecessary fields and set the required fields to be required. I removed the indexes on the FK fields since Access will build them automatically. Since I was running an action query in code, I included a macro to turn the warnings off and the hourglass on and a second to turn warnings on and the hourglass off. The hourglass is an annoying graphic feature. If the hourglass is on when you think it shouldn't be then run the "on" macro to turn warnings back on. I do this because it is CRITICAL that you don't leave warnings off accidentally and it is easy to do when you just turn it off without setting the hourglass on.
The code and queries I built are simple. You should be able to understand them but ask if you don't.
I made some assumptions.
1. there would be only the processes from the Process table and none could be added or deleted.
2. I calculated Late_Days in the query rather than storing it. I just did a date-date calculation. If it needs to exclude holidays and weekends, I can give you the functions you need.
3. Status should be a combo so I made one with just two choices. Make these whatever you want.