The real problem is that the LOGO! is only designed for integer values ​​(whole numbers in the range -32,768 to 32,767). Decimal places of any kind are always only for display purposes.

2 decimal places are displayed for the gain, but this is only optical. It's actually an integer, multiplied by 100. So a gain of 1.00 is an integer of 100.

If you set an amplification of 0.1 followed by an additional amplification of 2.25, the mathematical result is 0.225, but not in the LOGO!.
In the LOGO! then the following happens:
10/100 * 225/100 = 0.225. Can the LOGO! but not and rounds up to 0.23 because of integers, which then corresponds to a total gain of 0.23.
And with such a small gain, you get the relatively big jumps.

If I were you, I would choose a gain of 2.25 and one decimal place in the display. You can compare both variants in the attached example.

As you can see in the second example, ten times the amplification factor is used.
With the first variant, you get values from -40 to 140 after the analog amplifier, which corresponds to a display of -40 to 140.
With the second variant, you get values from -400 to 1400 after the analog amplifier, which corresponds to a display of -40.0 to 140.0 (if a decimal place is set in the analog amplifier).
If you want to use the second variant and, for example, want to use an analog threshold trigger, you must always have the decimal place in mind.