Hoping something here answers your question.
Adding an image in App Lab is Unit 2, Lesson 9 Code.org - Using Images
Unit 4, Lesson 9 explores what is possible in App Lab. “Before starting to design apps, we need to help students scope their expectations. Because students will eventually be prototyping these apps in App Lab, they will be in better shape if their ideas align with the kinds of apps that can be made using AppLab’s tools.” Code.org - Exploring UI Elements
This was posted under Unit 1, Lesson 8. Students are not creating an app in that project, but a poster. So they are not expected at this point in the curriculum to be creating apps. Awesome if they are!
If you are asking how to create movement in AppLab?
Perhaps, this previous conversation may help. Example code for ball movement in App LAb
If I still haven’t answered your question, please let me know more specifics about what you are trying to do.