I'm not really a web developer as such so I'm having difficulties with changing the way the shipping amount is calculated. I want to use a similar method that calculates by country and total order weight.

However, I don't want the charge amount to be multiplied by the total order weight to give the shipping total amount...so for example if the total order weight falls between weight bracket A and B, the shipping total is only the charge amount for that weight bracket and the method selected by the user
Method X: From 0kg to .250kg, charge amount is $4.30 - shipping amount $4.30
Method Y: From 0kg to .250kg, charge amount is $8.00  - shipping amount $8.00
Method X: From .251kg to .500kg, charge amount is $5.30  - shipping amount $5.30
Method Y: From .251kg to .500kg, charge amount is $8.00 - shipping amount $8.00

Oh, I hope this makes sense to someone! It would really be appreciate it if someone could help me out with creating a calculation