@conrad i use uPyCraft to transfer files to atom. You can also connect uPycraft with atom and use REPL (something like command shell) to use interactive micropython command interpreter). With UiFlow it is possible but you must first transfer libraries to /apps folder in flash memory and use advanced->execute->execute code to run appropriate commands, ewentually write raw code in Python </> tab. In this option code probably properly run only when you download it to device (not run with play button).
If i find some free time then i create custom block to scroll text using recently added Hardwares->Rgb->set atom matrixblock, but i must do some experiments with it.