Each IA MED course is linear meaning you must start at the first page and complete any required work before the system will allow you to progress to the next page.
Once on the page complete the required work or video (video are time-gated) then select the red "next" arrow at the top right of the page to move on. Once you have completed that pages requirement you will see the red"next" arrow at the top right become solid allowing you to progress to the next page.
For Video course pages you will need to have a solid internet connection throughout the video so the system can recognize the allotted time has been met to allow you to move forward and the red "next" allow to become solid.
Once you have completely progressed through your course and completed it you will then be able to move around freely without hesitation.
Using Chrome as your internet browser does seem to help out with this.
Lastly, if you could delete your temporary internet files and cookies, then log back into your IA MED dashboard and accept the cookies may help.
Thank you for choosing IA MED and stay safe!