Catering Integration
Create group called "Catering" and assign the necessary sections (which is the HL name for categories):
*Note the group name must* be "Catering" but the section names can vary
Assign any catering "Sections" to this group:

***Make sure to remove these "Sections" from the main menu if you intend to separate to catering only.
Order Fee
Under "Service Charges / Fees"
Make sure the Order Fee is NOT checked "apply post tax" (this will tax our order fee)
Service Fee
Under "Service Charges / Fees"
Create this fee to pass the Spillover "service fee" which adds a percentage of sale as revenue on top of order total.
Check to apply post-tax. (see J&S setup for example)