Update from March 10th, 2021
Starting from version 18.104.22.168, Plant supports versioning of files added to Sketch Cloud and Sketch for Teams. Please note that all users who get a copy of a project will only be able to save the file locally.
Processing of Sketch Cloud files by Plant can lead to inconsistency of information contained in both Plant versions and in Sketch Cloud, as well as cause false design conflicts.
To avoid this, our team decided not to support such files yet. We will continue to monitor the development of Sketch Cloud in order to offer a solution in the future that will not contain problems mentioned above.
At this point, in order to continue working with Plant and create a project use the following step:
1. In Sketch go to File > Save As...
2. Select On Your Mac tab > Save
3. Create a project in Plant