Weight Calculation Changes in 3.0 - why so drastic a change?

In my prior version of nop (2.65), I had my shipping calculations working perfectly. I used the by weight method where I could say anything between 0 and 10 lbs costs $10 to ship. Anything from 10.1 to 20 is $15.

Now however, I see the calculation is way different, so those same entries before are giving me shipping costs of like $2 and $3.

Is there a way to make it work like it used to?

Yes.  Only set these fields
Order weight from:
Order weight to:  
Additional fixed cost:

These should be 0
Lower weight limit:
Rate per weight unit:
Charge percentage (of subtotal):

(The change allows for more complex rate calc if needed - e.g. weight & subtotal%, etc)

I also found this and thanks for the answer.

I think the upgrade script doesn't handle this properly.
In my case I had to fix all the computation values.

if anyone interested this is the script I used

update ShippingByWeight  SET AdditionalFixedCost = RatePerWeightUnit, RatePerWeightUnit = 0
    WHERE RatePerWeightUnit > 0

Simple but might save someone else some time :)

Cheers