2002 E46 325Ci Convertible Electronic Issues PLEASE HELP

Hi - new to this community! Urgently seeking help.

I bought my E46 a year ago with no issues.

My thermostat went out and I went to get it replaced at a shop. After I got it fixed at the shop - all these issues started appearing.

Remote locking issues
Over the course of a few months, I noticed that occasionally the doors wouldn't lock via remote - only manually. Even after locking manually, the indicator light by the gear selector stays on even though all doors are closed. That's not really a big issue as I am still able to lock manually it's not too big of a deal.

Turn Signal Issues
Then more recently, occasionally when I used the car, the turn signal indicators would not indicate on my dash. No sound or visible light. Same thing with my fog light indicators - although I can hear the fuse when I'd toggle the fog lights on or off. Everything on the outside of the car would work, just no indication of what's going inside the car.

Convertible Top Issues
Recently, my expansion tank cracked and blew after a long drive. Totally expected and due for a change. I left the car in my driveway for a week or two (busy with work) and when I went to start the car to work on it, the convertible top would not go down. I ended up swapping a new expansion tank and upper radiator hose and fixed my cooling system issues. However, the convertible top still will not go down. It has a red indicator that lights up but doesn't flash. Nothing happens, no noises or anything.

I had a theory that since I installed an aftermarket radio, maybe it was drawing too much power and started the electronic issues. I uninstalled the radio and unplugged everything - nothing changed.

Car Shakes Now lol
Also note, it has not been 2-3 weeks since I touched my car and now it shakes when I start it, still all the same electronic issues. What should I do?

Any help will be much appreciated. Thank you

Albert