When you import a large model, or when you import a large set of models, you may encounter an out-of-memory error during the XDE model import process. You can take some steps to reduce your chances of encountering this memory error.
Whether you encounter an out-of-memory error depends on many factors, including, but not limited to, the size of your XDE model and how much RAM your machine contains. If your XDE model is collectively greater than 200 MB (including all referenced models and subunits), there is a higher risk of encountering an out-of-memory error during the import process even if your machine has a 2 GHz processor and a sufficient amount of memory.