Based on the provided files and the given hint, here are the identified issues with the dataset:

```json
{
    "issue": "Missing task configuration file",
    "evidence": "No task_<task_type>.json file is present in the submitted dataset. The expected file structure, as per DATASET_SUBMISSION.md, should include one or more task configuration files.",
    "description": "According to DATASET_SUBMISSION.md, each dataset should include task configuration files, such as task_<task_type>.json, which store information specific to a task. These files are missing in the submission."
},
{
    "issue": "Missing urls.json file",
    "evidence": "No urls.json file is present in the submitted dataset. The expected file structure, as per DATASET_SUBMISSION.md, should include a urls.json file for cloud-stored .npz files.",
    "description": "The DATASET_SUBMISSION.md specifies that a urls.json file must be included to provide download links for the cloud-stored .npz files. This file is missing in the submission, which prevents the retrieval of necessary data files."
}
```

### Detailed Explanation:

1. **Missing Task Configuration File**:
    - **Evidence**: The submitted dataset does not include any `task_<task_type>.json` files, which are essential for specifying the tasks related to the dataset.
    - **Description**: The submission guide in `DATASET_SUBMISSION.md` clearly states that these files are required to store task-specific information, such as data splits and node labels for classification tasks. Their absence means that task configurations are not properly documented.

2. **Missing urls.json File**:
    - **Evidence**: There is no `urls.json` file in the submission, which is supposed to contain download links for .npz files stored in cloud storage.
    - **Description**: `DATASET_SUBMISSION.md` mentions that for datasets with large data files stored in the cloud, a `urls.json` file is necessary. This file should map each .npz file to its corresponding download link, ensuring that all data components are accessible. Without this file, the dataset is incomplete and cannot be fully utilized.