On the Subject of Spelling Buzzed

If I were a bad speller, I wouldn't be sitting here discussing it with you, now would I?

• This module has seven hexagonal keys with a letter printed on each one. Use the letter keys and the round Submit button to submit a valid word in each of three stages. There are many possible valid words.
• Someone's spilled drink has caused the module circuitry to malfunction. Before checking if your word is valid, the circuitry shifts each letter around the Alphabet Dial by a certain amount of spaces and in a certain direction (either clockwise or counter-clockwise). A letter can only be shifted to some letter in the same ring of the Alphabet Dial — for example, a vowel is always shifted to a vowel.
• At each stage, read the BAC (binary alcohol corruption) percentage on the display. Using the BAC percentage and the rules on the next page, determine the shift amount and shift direction.
• A word is valid if all of the following are true:
  • It is a common English word that is not vulgar.
  • It is between four and eight letters long, inclusive.
  • It contains the shifted center key letter.
  • It has not been submitted in a prior stage.
• To clear your input and show the BAC percentage on the display, press the square Reset button.

Shift Amount

Below, the BAC value refers to the BAC percentage multiplied by 1000.

• If the BAC percentage is less than 0.020, and there is a lit indicator with label CLR or an unlit indicator with label TRN, then the shift amount is the BAC value modulo two[1].
• Otherwise, if the BAC percentage is less than 0.050, and the DRUNK score[2] is greater than or equal to the SOBER score[3], then the shift amount is the BAC value modulo three[1].
• Otherwise, if the BAC percentage is less than 0.070, and the number of batteries is greater than the number of completed stages on this module, then the shift amount is the BAC value modulo five[1].
• Otherwise, if the BAC percentage is less than 0.100, and there is an indicator whose label contains a letter in the word CHEERS, then the shift amount is the BAC value modulo five[1], plus two.
• Otherwise, the shift amount is the BAC value modulo seven[1], plus one.

Shift Direction

• If the module is not on the third stage, and the last digit of the BAC percentage is even, then the shift direction is clockwise.
• Otherwise, if the BAC percentage is less than 0.060, and one of the letter keys has the letter O printed on it, then the shift direction is counter-clockwise.
• Otherwise, if the serial number contains the module's current stage number, then the shift direction is clockwise.
• Otherwise, if the BAC percentage is less than 0.130, and there are less than three port plates, then the shift direction is counter-clockwise.
• Otherwise, the shift direction is clockwise.

[1] To compute the BAC value modulo N, subtract N from the BAC value until it is at least 0 and less than N.
[2] The DRUNK score is the number of letters in "DRUNK" that are printed on the letter keys.
[3] The SOBER score is the number of letters in "SOBER" that are printed on the letter keys.