I didn't read all your post. I assumed you had a bike that didn't run. Here in the USA, I can go to a Batterys Plus franchise down the street, where they will load test any kind of lead acid battery and even replace the battery in my Iphone. Nearby is an Advance Auto shop and also a Trak Auto that will load test car batteries. Scooter battery is no different. You must have Canadian Tire, etc, and also scooter shops. WIth lead acid packs, the time will come when you need a place you can trust to do an honest load test.
If the bike runs, and you got 12v, your light issues are due to flaky wiring, dirty switches, blown fuses, burnt out bulbs.
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