On the Subject of Not Emoji Math

Math is easy. But is it?

Decipher the characters on the display into letters, unscramble the word, and find the unscrambled word in the list below.
Each word has a corresponding number and each letter in the serial number corresponds to a function.

Apply each function from left to right to each successive value, starting with the number corresponding to the unscrambled displayed word.
Take the last four digits of the output of the last function. Each digit corresponds to a letter in the scrambled word on the display.
Rearrange the four digits into the positions that match the unscrambled word and remove any initial zeros. This is the code that must be entered into the module using the keypad.

Once a code is entered, press the equals button to submit it or the minus button to clear it.

APEXATOMBITSBURNCHEWCOZYDASHDRUMECHOEPIC
78911825645138526383019754625
FIVEFLUXGNAWGYRIHAJIHELMIAMBITCHJAWSJUMP
55112179098621440325709187129
KEYSKNOTLAZYLIMEMUONMYTHNEXTNOVAOGREONYX
866439567115923967823747095
PICKPOEMQUAYQUIZROSERUBYSNOWSURFTOMBTWIN
26835996111027139961289834252
UNDOUSERVERBVOIDWAVYWRAPYEARYUCKZEROZINC
26717410133928521144999654
LetterEncodingFunction
A:)Add the number of characters in the encoded word.
B=(Multiply by two.
C(:Add the sum of the alphabetic positions of the letters in the serial number.
D)=Add the sum of the numbers in the serial number.
E:(Multiply by six minus the number of letters in the serial number.
F=)Add the sum of the alphabetic positions of the first letters of each indicator label.
G):Add the first number in the serial number times ten to the power of three minus the number of applied functions.
H(=Multiply by the number of unapplied functions.
I:|Take the difference between the input and ten times the initial value.
J|:Add the number of distinct letters on the indicator labels.
K=|Add the sum of the digits of the input.
L|=Add the sum of the alphabetic positions of the last letters of each indicator label.
M:-)Add one thousand.
N=-(Take the difference between the input and five thousand.
O(-:Shift the digits once to the right.
P)-=Shift the digits once to the left.
Q:-(Add the square of the sum of the numbers in the serial number.
R=-)Multiply by the digital root of the input.
S)-:Reverse the digits of the input.
T(-=Take the difference between the input and ten thousand.
U:-|Arrange the digits of the input in ascending order.
V|-:Arrange the digits of the input in descending order.
W=-|Arrange the digits of twice the input in ascending order.
X|-=Revert to the initial value and add the number of applied functions.
Y(:<Add the initial value.
Z>:)If the input is even, divide it by two.
Otherwise, triple the input and add one.