Many problems that OpenShot users experience with the application are resolved by resetting OpenShot to its default settings.  Open your file manager (File Explorer, Finder, Files, etc.) and delete the C:\Users\(USERNAME)\.openshot_qt folder (~/.openshot_qt in macOS and Linux). Removing this folder removes settings and many things that can, in theory, become corrupt. OpenShot automatically recreates the folder with the default settings when you relaunch the program. This folder is not deleted when the program is uninstalled, so your previous settings are saved, often causing projects to fail.