First off, the major problem is the water leaking in when it rains. The spongy floor may be due to the water leaking in when it rains. If the spongy floor is near the area where the water leaks are, then it is probably water damaged. If so, this will not improve, only get worse. So the big problem is the water coming in when it rains. Document this condition, video the water coming in while it is raining. If there is as much water coming in as you elude to, and the spongy floor is in the same area, then this TT needs to be taken back to the factory and fixed from the floor up.
If you are blowing things out of proportion, then you're just experiencing normal new TT slip shod construction. Get the issues fixed and move on.
To determine which is which, you need to find someone that you can rely on, that has good experience with TT's and water damage and go from there.
As far as the electrical is concerned, it sounds like you are trying to run to much stuff at once. 30 Amps is it. The breaker can be tested to ensure you are getting the full 30 Amps. After 30 Amps, the breaker is doing its job and protecting you.
