Sure, I can help you write a test case generator for the "Indian Puzzle" problem. Here's a Python script that generates random test cases adhering to the given constraints:

```python
import random
import string

def generate_grid(H, W):
    grid = []
    for _ in range(H):
        row = []
        for _ in range(W):
            choice = random.choice(['.', '#'] + list(string.digits) + ['+', '-', '*', '/', '='])
            row.append(choice)
        grid.append(row)
    return grid

def generate_char_list(n):
    characters = random.choices(list(string.digits) + ['+', '-', '*', '/'], k=n)
    return characters

def tcgen():
    datasets = []

    while random.random() > 0.1:  # Randomly decide when to stop generating datasets
        H = random.randint(1, 10)
        W = random.randint(1, 10)
        
        grid = generate_grid(H, W)
        
        n = random.randint(1, 10)
        char_list = generate_char_list(n)
        
        datasets.append((H, W, grid, n, char_list))
    
    return datasets

def format_dataset(dataset):
    H, W, grid, n, char_list = dataset
    formatted_grid = '\n'.join([''.join(row) for row in grid])
    formatted_char_list = ' '.join(char_list)
    return f"{H} {W}\n{formatted_grid}\n{n}\n{formatted_char_list}\n"

def main():
    datasets = tcgen()
    for dataset in datasets:
        print(format_dataset(dataset))
    print("0 0")  # End of input

if __name__ == "__main__":
    main()
```

### How the Generator Works

1. **Grid Generation**:
   - Randomly determines the height (`H`) and width (`W`) of the grid, each between 1 and 10.
   - Fills the grid with random characters from the set {'.', '#', '0'-'9', '+', '-', '*', '/', '='}.

2. **Character List Generation**:
   - Generates a random list of characters (with length between 1 and 10) which are digits ('0'-'9') and operators ('+', '-', '*', '/').

3. **Dataset Generation**:
   - Continues to generate datasets until a random stopping condition is met.
   - Appends each dataset to a list of datasets.

4. **Formatting**:
   - Formats each dataset according to the problem's input specification.
   - Joins the characters and grid rows into the appropriate string format.

5. **Main Execution**:
   - Generates and prints all datasets.
   - Ends the input with "0 0" to signify the end of input as specified.

This generator ensures that each dataset adheres to the constraints and format specified in the problem statement. Feel free to adjust the random stopping condition and character generation logic to better fit specific needs or patterns.