As i clic on the first exercice link, a log popup ask my User Name and password.
I input my email as User Name and my password but the logon failed.
I 've also tried my first Name and Name and also only my Name but got the same result.
As I fill in the "forgot password" dialog My User Name is rejected.
The user name and password you enter should be listed in the exercise in which you are completing at that time. I do not know which version of the BAE course you are taking however if you were taking the BAE 7.4 you would see the following image when you went to do the first exercise:
In this case you would use author.hrapps/rules to login to the exercise system. Please note to look at the table in the scenario section of each exercise as the login may be different.