I have absolutely no idea what a self-watering container is but from the sound of it it is not really something for someone new to gardening. I hope others in this forum could help you out.

My overall guess would be a nutrient balance , likely nitrogen deficiency issue as this could cause the issue of yellowing of the gourd leaves and the yellowing of your okra too. For the beans if the leaves are pale this could also explain it.
I would add nitrogen rich compost material like coffee grounds, egg shells etc
The spots on the beans i am not sure, is it like a mildew spot?

That photo doesn't look like normal nitrogen deficiency to me. I think it may be a potassium or micro-nutrient deficiency. I'm just guessing without knowing more about what they're growing in.

The beans sound to me like aphids and spider mites. check the underside of the spotted leaves for small red arachnids. My bitter melons took a long time to do much of anything but the weather warmed up for the past couple of months and I have fruit bursting all over now.

You might want to direct your question to the container garden forum.

The leaves of our bittergourd plant are drooping and some leaves at the bottom are turning yellow . Kindly tell where things are going wrong.