Re: Extension cords, UPS, and power strips safety
The code does limit how much load can be served from any one receptacle outlet and on any one branch circuit. However, the user of the code hardly ever has control of owner use of the electrical system.
Though your example seems excessive in the amount of appliances and equipment being served by one circuit and one receptacle, the overall load seems minimal.
What bothers me is all the use of extension cords and plug strips, however you claim this setup is only temporary and broke down after relatively short use. I think splitting up the loads and reducing the use of extension cords would certainly add to overall safety and more efficent operation of the equipment.
Bryan P. Holland, MCP
NEMA - Codes & Standards