One Shipping Method free If Total Shop is > 100eur

Hi,
I have multiple shipping methods configurated: 1st Class, 2nd Class, courier etc.

I Want if Total Shop is > 100Eur Shipping "1st Class" is free, Other Shipping with pay.

Is possible?
Do you need modify the source code or by the plugin?

I have tested this plugin "Shipping by Total" but I can not seem to work:
https://www.nopcommerce.com/p/669/shipping-by-total.aspx

Thanks!

"Shipping by Total" should work for that.  First set up multiple Shipping Methods ("1st Class", etc.), then configure the rules with correct Order Total From and Order Total To for each method.

I Tested the component:

Shipping method "1st Class"
Order total From: 0
Order total To: 9999999999
Charge amount 5Eur

But in Cart This Shipping methos is always 0 :(
I do not understand why

I solved!
The product in the Cart have Spedition free! i unchecked this option and the plugin worked well!

Yes, you have to be careful with the various Free Shipping settings:
On Product
For Customer Role
Free Over $X cart amount
Discounts