I am sorry that is definitely not speaker look alike. It is supposed to look like a battery. But the my it doesn't make difference to the problem.
Answering your question one at a time.
Once the program is loaded. Using a BUFFALO monitor program I would type go 7000 to run the program, Where 7000 is a hex and address from where my main subroutine starts.
Your second question, LDAB #$40, is the instruction that will initialize CGRAM. $40 corresponds to first row of 5x8 pixel map. So, $40~$47 for 8 rows. Last row is 00 for cursor.
I am newbie but I have some assembly and now trying to play around. I tried following the instruction in the website below but its for different MCU.
w w w.8051projects.net/lcd-interfacing/lcd-custom-character.php