Customized Price Shipping

Hello--
I need to use the price shipping method. However, I need to modify it so that the cost is also based on a percentage of the order total. For example, if the order total is less than $300 then I would use the existing cost categories but for orders over $300, I need to use a percentage for the shipping charges.
Is there a way which I can "hack" the code and make such a modification?
This a must have modification in order for me to use eShop for our store front!
Thank you for the help!
Don
Here is a sample of the shipping cost which we need to use:
When total is: Standard S&H
$20.00 or less $8.00
$20.01 - $50.00 $11.00
$50.01 - $80.00 $14.00
$80.01 - $300.00 20% of total order amount
$300.01 or more 15% of total order amount

Hello Donald,

Price Shipping method has already support percentage. So instead of entering 20, you should enter 20%.

Please try and let me know if it works as your expect.
Sincerely, Giang

Hello--
Thanks for the reply; it is appreciated.
However, the Price Shipping configuration does not function as I would expect according to the field tips. Attached is a snippet of my configuration. No matter what the shipping total is, it always uses the last cost figure which is 15%. Do my entries look correct? If so, then what am I doing wrong?
Thanks for the addition help.
Don

Hi again Don,

It looks correct. Please submit a new ticket to EShop category to send me the super admin account to your site so I can help you to check the reason why it does not work.

Sincerely, Giang

Thanks for the help. However, I found the problem. The total range must start with a zero; 0;8;11;14;.....etc.
Best regards,
Don

That's fine Don!

Have a nice day!
Sincerely, Giang