Hi,
The FEDEX api uses Soap and the HikaShop fedex plugin use it.
I am sorry than your hosting does not allow the SOAP plugin but it is not more CPU intensive than other things in PHP.
And more than that, make the SOAP request manually in PHP (which will be highly time consuming for the development) will use more CPU than the PHP Soap module (interpreted script VS native code).
If someone wants to rebuilt the plugin with another system and do not use the FEDEX Soap API, we will be happy to integrate the plugin in HikaShop but the actual plugin is working fine.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.