Creating multiple graded assignment links is a common mistake, and it creates massive headaches for both instructors and students. Because of the way LTI works, we can only pass back grades to one grade column at a time, and we always pass back students' current grade for the entire board (not a "weekly grade" or assignment grade). If you attempt to create multiple graded assignment links associated with multiple grading columns, students' grades will pass back to the column associated with the assignment link they most recently clicked. Hence, students' current Yellowdig grades will be scattered across different grading columns depending on which link they clicked last. This creates significant downstream problems for instructors and students and consumes your institution's Yellowdig support resources.
Creating an assignment link associated with a grading column that is "out of 0" is not a solution; in fact, it creates an even worse situation for everyone involved. Because Yellowdig passes back grades as a proportion, if a student clicks such an assignment link, that student's LMS grade will become 0 (since anything times 0 is 0), and their LTI connection to the "actual" grading column (namely, the grading column that is not "out of 0") will be effectively severed. In other words, students' Yellowdig grades will be wiped from their LMS.
Remedying problems created by multiple grading columns can be very difficult, since it requires widespread cooperation from students. Because of the way LTI works, we cannot simply "push" students' correct grades to your LMS; rather, each student needs to click on the same assignment link. If you decide to create multiple assignment links, we may not be able to achieve satisfactory solutions to the problems generated by this decision.
If you are confused about any of this, please reach out to Yellowdig at firstname.lastname@example.org before setting up your Yellowdig Community. You will save yourself, your students, and your support team a lot of unnecessary troubleshooting.