Very often when a project was started for some time, a lot of model elements are created, and most of them are placed at root. This not only makes the searching of model elements become difficult, but it also slow down the application because Visual Paradigm tries to load all root level model elements on start up.
To solve the problem, it is recommended to keep the root clean by organizing project data with models or packages, while model is more preferred. When you right click on the project root in Model Structure tree in Project Browser, you can see the menu Model, which lets you create a model. Read more