No insurance coverage means "don't drive the car". I would say that if your girlfriend has insurance coverage on the car and she allows you to drive there would not be a problem. This is unless you had been formally excluded from coverage by her insurance company.
Usually it does, you would have to check to see if you have a broad coverage policy or not.
No, your insurance will cover the occasional driver as long as they are licensed
Yes. It covers you no matter where you are as long as you are paid up for your coverage and it is an active policy.
Some insurance companies like Progressive will cover a non-owned vehicle meaning a vehicle in which you have no legal or financial interest. Check around if your insurance company does not provide coverage to non-owned vehicles.
Not Likely, Home Owners insurance piolicies typically exclude coverage for concrete structures such as Sidewalks, Patios and Driveways.
It really depends on the type of coverage you have. Normally if that person had permission to drive the vehicle, you have full coverage/collision insurance, and that person was at fault your insurance will cover damages. If someone else caused the accident, you would still receive damages from their insurance if they were insured. Sometimes however the driver's insurance would cover your damages under certain circumstances. As always, it is really best to ask your insurance carrier or refer to your most recent coverage letter from the company.
Your personal auto coverage will not cover their vehicles. What they are probably asking for is to make sure you have coverage in case you drive your vehicle on errands or such for the company. If you go to the post office to get the company mail your personal auto insurance will be the primary insurance and then if they have an endorsement to their insurance called "hired and non-owned auto" it will provide secondary coverage over and above your coverage to protect them in case of an accident. Their coverage insists that you as the employee have primary insurance on your vehicle. Also note that the company insurance will not pay for damage to your vehicle.
It may, You really just need to discuss it with your Insurance Agent. Some homeowners policies do provide coverage for certain types of Sink-age and some do not.
An SR22 isn't a policy or a coverage. It is a notification to the state that you have coverage.
You can but you will be breaking the law.