Volvo newcomer with some questions

Hallöchen, I have now joined the group of V40 owners as well. It is a 97er 1.8 automatic 170Tkm I like the car very much, but I have a few problems or questions about you for many years. 1. I find the brake relatively spongy, but what I have read is normal. Is that true or can you recommend to me reasonable other brakes? 2. Something is loose in the amature board at the front left, which is soldering/klappert like sour with cold engine in the condition that it is not nice any more. When driving ice out. Is as said only when driving stage is in place and the engine is cold, so relatively high standing gas has 3. somehow I have not quite understood the ZV. Open and close all the doors as they should, but I can only open and close the trunk flap with the key. Is there any kind of fix there? Up to now I have only read about non-opening or closing doors. 4. I can also not close my tank lid. No matter how I can close it all, I can open and close it again with the key. I can’t find my little help.