Put the eggplant, zucchini, squash, and tomatoes in 1 layer on a baking sheet or baking sheets, drizzle with olive oil and sprinkle generously with salt. Roast until the vegetables are soft and pliable, about 20 to 30 minutes, turning them halfway through the cooking. Remove from the oven and allow to cool. When cool enough to handle transfer them to a cutting board and cut them into 1/2-inch pieces.
Heat a large skillet over medium-high heat and coat the bottom with olive oil. When the oil is hot, add the onion, crushed red pepper and season with salt, to taste. Saute until the onions are soft, about 5 minutes. Add the peppers and season again with salt, if needed. Cook until the peppers are soft, about 5 to 10 minutes.
Add the roasted vegetables to the pan along with the vinegar, marjoram, and thyme. Toss well to coat and add 2 to 3 more tablespoons olive oil, if needed. Taste to check the seasoning and transfer to a serving platter or bowl. Voila!