I assumed that the ingredients for making kalabasa ketchup could be the same as tomato ketchup or banana ketchup. I chose banana ketchup recipe as model.

Here are the ingredients:
250 g kalabasa, no peel and seeds, sliced
1 small onion, chopped
1/2 red bell pepper, chopped
4 cloves garlic, minced
1 cup water
3/4 cup vinegar
250 g second class sugar
1/4 tsp salt
1/4 tsp paprika
1 tsp ground pepper
1 tbsp cornstarch

Procedure:

1) Boil kalabasa slices in water until tender. It should take less than 15 minutes.

2) Mashed it thoroughly with spoon.

3) Place onion, garlic and bell pepper in mortar. Then pound it with pestle to a puree consistency. Add it to mashed squash. Dissolve cornstarch in small amount of hot water then add it to mixture. Add the rest of the ingredients.

4) Place over a medium flame and stir continuously until tacky or similar to ketchup consistency.

5) Place in clean bottle. Keep refrigerated. No preservatives added so shelf life is short under ambient condition.