In MOODLE, there is a timer in mod/lesson/timer.js
This timer is used for the "time limit" function, and it has a maximum time limit, so that if you spend too much time, you can't go forward.
We need this function redirected to "timespent", and we need it to have a minimum time they must spend in the lesson before they are allowed to move on. The timer much keep accumulated time, just as timespent already does.
All of the files are there, we just don't know how to redirect it. This will be a quick and easy job for someone who knows MOODLE thoroughly, and we are willing to pay $100 for what will take the right person probably 10 minutes at the most.
DO NOT APPLY IF YOU DO NOT UNDERSTAND THE MOODLE TIMER IN MOD/LESSON/TIMER.JS