In the spring semester, I used the “Tests and Quizzes” tool in Sakai to distribute my final exam. It was an essay exam. Under “event log” I could see the entry time and submission time. “Entry time” indicates when the student opened the exam and “submission time” when they uploaded their answer. (I also created two versions of the exam to discourage collaboration — if one student opens the exam, only about half of the other students will benefit from viewing it. I did not observe an indications of this type of collaboration.)
I also used Tests and Quizzes in Sakai to administer my exams. I had separate assessments for the multiple choice part of my exams (where questions were drawn from pools of 3-4 times as many questions and the order of the questions and answer choices were randomized).
I also used it for the short answer/graphing part of my exams. I used the file upload question type and had students handwrite or type their answers and save to a one-page PDF, which they could then upload to Sakai. From there there is a button to download all submissions and then I was easily able to upload them into Gradescope for quick and easy grading. If you do this, make sure you give students an opportunity to practice creating a PDF and uploading it to Sakai. If students do not upload a PDF it is a pain to get their responses into Gradescope, but the only students that had any issues in my classes were those who did not take the practice exam to practice uploading a file to Sakai. I could have had students upload their answers directly to Gradescope, but then it would have been more difficult to enforce a time limit, give different time limits to different students, or give students different versions of the same questions.