From the left menu, expand "Files section" and select a storage. Make the Folders tree visible. Go to "Android/Data" which contains many folders. Go to the last item in "Android/Data" (in the folders tree) and click on it. Then press the Up key very quickly or continuously. At some point, after MPE starts opening a lot of folders, it will crash. The app just closes. IMO, if there is no better way, it should wait for the first folder to be processed and then try to expand the next one.
I've also noticed that it takes some time to open a folder and when it does, if it contains subfolders, it selects the first child. If in that time the user has clicked on another folder, his selection is lost (it is transferred to the first child of the previous folder instead of the user-selected one). A suggestion here would be when selecting the child folder to add a small check: "if my parent is still the selected folder, then select the first child".