and, may I suggest the name for the score multiplication button "Amplify Counter/ Amplify Trigger"?

Seems the best way to use it is to hit the button once at the beginning of the stage and let it pile up as long as the mizugi keeps coming. Since the amount of renewing the counter (and increasing the multiplication factor) is limited (you're given 5 per stage, more are given instage, but not sure how), use it during bosses when the big red "!" mark is flashing. That way, the counter can be kept insanely high. Dying however, seem not to reduce it all the way back to 0, but divide it either by 2 or 4, depending.

I tried running it in japanese locale too and the same happened

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About Bonus Points

● Normal Points
Each hit on an enemy unit gives you 10 points.

● Core Parts Bonus
When enemy crafts medium-sized and above are destroyed, their core fragments (Red) will scatter and float around. 50 bonus points are given to each attack shots at these fragments.

※ There is no judgement for attacking core fragments.

● Bonus Point Button (I couldn't come up with a cool name for it, please tell me if there's anything better)
When invoking this (By pressing the Y button), you will score double points in that fixed period of time.
If you activate it again while it is already activated, the bonus points will multiply by 4x, and 4x will become 6x, etc..., each consecutive activation will increase the bonus point increment rate.

At the beginning of each stage, the number of enemy units which hold the Bonus Gauge Special is fixed to start with "3".
Each time you get a green pantsu from enemies along the way, it will keep increasing the gauge by +1.

● Swimsuits
When destroying a medium-sized or larger enemy craft during activation of the [bonus time] by pressing the Bonus Point button, it will appear.

Each swimsuit gives you 1000 points + 300 increment to the bonus gauge.

※ Important
The MAX for the Bonus Gauge is 1200, and each frame will automatically reduce the gauge by -1.
Each time the Bonus Gauge hits MAX, the increment ratio is increased by 1.

A Team [Balance Type + Defence)

Control Unit (Yoshika)
[B button] ...Magic Shield
(Usable when gauge at MAX, gauge will auto-refill, refills faster when not shooting)
Bomber type that blocks enemy bullets/lasers

Option (Lynette)
Fires Piercing Bullets (when Reene comes into contact with enemy bullets and units)

Option (Mio)
Sword Slash (when Mossan comes into contact with enemy bullets and units)

B Team [Attack Type + Speed Attack]

Control Unit (Gertrud)
[B button] ...Steel Frame
Destroys enemy bullets, can be used to destroy enemy units too.
(Speed lever neutral + B button) ...Steel Frame will circle around Gertrud when moving
(Speed lever pressed with specific direction + B button) ...Steel Frame will be fixed at that angle

*This team cannot reduce movement speed

Option (Erika)
Storm Rush Attack (when Erika comes into contact with enemy bullets and units)

Option (Minna)
Magic Shield (when Minna comes into contact with enemy bullets and units)

C Team [Special Balance Type]

Control Unit (Charlie)
Unification...If seperated, will join with Francesca when come into contact
[B button] ...Fires Francesca if joined (Special Attack)
*When seperated, holding down the B button will pull Francesca towards Charlie

Option (Francesca)
When firing Francesca (Nullifies enemy bullets/lasers + can attack/shoot), a blue magical trail will remain on-screen. Even so, Francesca can still nullify enemy bullets/lasers and attack/shoot

D Team [Special Attack Type]

Control Unit (Mio)
[B button] ...Sword Slash
Nullifies enemy bullets/lasers, attacks (depletes gauge)
[Counter Attack] ...Auto-activate depending on Sword Slashes of enemy bullets/lasers/units

Option (Perrine)
Lightning Shock nullifies enemy bullets around Perrine (when Perrine comes into contact with enemy bullets and units)

E Team [Balance Type + Attack]

Control Unit (Eila)
Unification...If seperated, will join with Sanya when come into contact
[B button] ...Fires Sanya if joined (Special Attack)
*When seperated, holding down the B button will pull Sanya towards Eila

Option (Sanya)
When joined with Eila, missile attacks gain homing function and the ability to nullify enemy bullets

Option (Yoshika)
Magic Shield (when Yoshika comes into contact with enemy bullets and units)

*downloads game*