We are preparing a full wiki which will be linked shortly.

Yes, go crazy. We will share some examples to help you out.

No, there is no need. Livegrid is primarily a plug and play product which requires zero operation and connectivity. However if you are itching to customise it and try other things with it, you have to enter development mode which will unlock the WiFi and extra features. But for most users, this is not essential.

Around 120mAh without WiFi and 700mAh with WiFi.

No, but you can easily plug a standard USB power bank, just make sure it can output 5V 3A(15 Watts). A 10,000mAh power bank will run the panel for almost 25-50 hours depending on the brightness and operations. We are working on adding a compartment in the back where you can place the battry securely.