Chained constraints

[liquid]

Life brings a lot of experience, more than a developer may predict. In my timetable, I needed something like "three activities are consecutive". Assuming "consecutiveness" relation is transient, if you declare that activity_1 and activity_2 are consecutive and activity_2 and activity_3 are too consecutive there should be relation that activity_1, activity_2 and activity_3 are consecutive. Additionally, activity_3 must end students day. In theory, but program gets stuck after a small percent of placed activities.
My workaround was this: activity_1 and activity_2 are consecutive, activity_3 must end students day and that three activities were grouped. The program then solves the timetable but it needs more time to do it.
The question is: is the program aware of chained activities and can warn a user that they may lead to no solution?

[Liviu Lalescu]

Many constraints are combined, like min/max hours daily and max gaps. But I did not care for your situation, I hoped it will be OK automatically. Unfortunately, it isn't 

You might use group the activities in the initial order, for A1, A2, and A3. But I am not sure this is the problem.

[Vangelis Karafillidis]

So, the activities A1, A2 and A3 should be place on the same day (any day), continuously in a three-hours block and the activity A3 should be the last one for the students set, right? Is this your problem or something different?