Speed will be based on your Internet Service Provider (ISP), the modem used, devices used, and the router used. If the ISP provides 100 service, that is what you can expect for a wired connection and...

Try deleting (forget) the network on your device and then re-add it.

I would go with a pure mesh router system over using an extender and router combo. That is what I plan to do when I replace my current router. I also have an extender to cover a dead spot in my...

I do not understand why either. You may want to try the EN forum as this is the US one. They may have encountered the issue since they see the EU version a whole lot more....

Check the label on the router and see if it has a country code as your router may not have been a EU model. This may help https://www.tp-link.com/us/choose-your-location/

Sounds great. Have you done any recovery using the BackupBundle?