Moodle in English

It´s as you write in your first sentence. I tried all different settings. There are two alternatives as long as i can see:

1. different assignments för different groups (with different dates)
2. delete the  "until date" under "restrict access" and use "due date" under "availability" instead

My teacher changed to alternative 2. The different groups have to submit with a week interval. Due date is set to the second groups date. 

good luck with  reinstalling