Quest Learning Modules offer the ability to regulate the amount of time a student spends on an assignment. Do use this setting, create a new assignment, select learning module, and enter in the full window during which students could take the exam.
Below this you will be given the option to set the amount of time students will have once they progress past the instruction slide of the learning module. If you do not want your students to receive immediate feedback be sure to also check the 'test mode' box.
Any instructions can be written in, and the timed assignment is created once you click the blue 'create' button at the bottom of the screen.