I assume if you know Java you could increase the digit limit in the code, otherwise no idea, sorry! I want to know as well...
Minecraft has no age limit.
There is no limit.
There is no age limit, as long as you buy an account you have one.
There is no limit.
y=256.
For spending increase my credit limit
It depends. All electronics can be misused. Minecraft can be unhealthy if that's all you do. Just limit your time on it.
The limits are by character (letter, number, etc) not by words. There is a 420-character limit for Status updates and a 1000-character limit for wall posts. Hope that helps!
There is no way to cancel the limit.
It'll probably crash.
minecraft has no age limit, neither does servers. some may warn you that there is swearing etc in them though.
Yes you can, the demo just has a time limit.