If you have a salt water pool then the chlorine generator is there to convert the salt into chlorine to keep up the chlorine content of the pool. However if you don't have one of these or it is broken down you can always add chlorine directly to make up the shortfall until the necessary repairs are done.
Yes you can use an Ozone generator and a Chlorine generator together. The Ozone generator will actually extend the life of the cell on the Chlorine generator because the ozone takes care of the bulk of the oxidation workload, thus the Chlorine generator does not need to be run as hard.
It sounds like the chlorine generator is broken
That depends on the size of your pool and the level of salt your chlorine generator needs to properly function (usually 3200-3400ppm). If you do not have a quality salt test, I recommend bringing a sample of your water to a local pool store to be tested. Bring your chlorine generator's manual with you and they will help you find where it shows how much salt to add. If your pool has been low on chlorine for more than a day or two, or if the water is cloudy or green, you will need to add some liquid chlorine to assist the chlorine generator in clearing it up.
Adjust your chlorine generator levels.
Do you have a chlorine generator? No.
Yes you still need a pump and filter. The saltwater system generates chlorine and eliminates the need for chlorine tabs. You will still need to keep the water balanced and continue normal pool maintenance.
Yes, just install the chlorine generator and add the salt. Your new system will replace the need for residual chlorine.
You may need to go to a much lower setting or turn it off for a brief period.
No only for the amount of time that it takes to generate enough chlorine an average this is a minimum of 6 hours per day.
Yes
Yes. The salt is run through a chlorinator that changes the salt to chlorine. It won't do it by itself so you have to buy the generator to do this.
I really don't know.