A big thank to ChrisMicro
I just got my LPC810 and had a working blinky almost without trouble.
Here is the procedure I used
Download Arduino 1.5.7
Download Chris's zip-file from post #1
From that download copy LPC8 folder and tools folder to: <path programs>Arduino/hardware/arduino
I use a 3v3 usb/serial converter so that can be directly connected to the chip so next steps:
Disconnect the power from the chip and connect pin 5 to ground to go into programming mode
Compile and upload the sketch.
Disconnect power and pin 5 from ground
Reconnect the power, and the sketch should start
I was a little confused about the pin numbers but they are here:http://vilaca.eu/lpc810/
BTW you have to have python and Flasmagic istalled too (used for the upload)
My OS is Windows Vista