Hi,
All depend on the type of custom field.
The order custom field can be read directly in the order object. For the user custom field, you have to read them in the "order->user".
Displaying a custom field might require the hikashop field class to format them. The custom field only contains the value and if you have some special custom field (like a drop down) you will want to display the associated string for the value.
That is the goal of the function "display" of the field class.
If you do not have special custom field (text / textarea), you can display the raw value, it will work fine.
If you look at the HikaShop code if you want to have sample on "how display a custom field". But like said just before, it will depend on the type of the custom field.
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.