It is possible to put one or more people as project administrator, so you can update, create links among other things. Since at the moment only the creator can do it.
Thanks for reaching out to us. We are working on this issue and maybe in future releases you will find a solution. As per the current feature, Updating the prototype link is only possible on the machine with which the .xd file was created.
Let us know if that helps.
We will try our best to help.
Jyoti Ranjan Behera