About online/cloud saving, I have spent my almost 10 days to it. That was really confusing if you never did it before. I had to read every documentation and watch tutorials but most of them was outdated and useless.
Most frustrating thing is you don't get proper help and support if you are not paying them(minimum 300$ per month). I have finished entegration of cloud and saving datas from players. Only loading function was giving me an error. I contacted with support and wrote it to forums, 5 days passed with zero response. So I trashed my ten days of work. One of my friend is gonna help me with it soon with different way of aproach. I hope cloud system will be done end of the this month.
You should be able to purchase tap upgrades from the red panel on the right