The LEDs are current-driven devices --they are not voltage-driven ones.
Anyway, the schematic of this device seems to be very simple:
The four input resistors are 470Ω/0.5W each and they form an input bias resistor of 1K88/2W, which feeds the LED with a current of 8..21mA minus 1mA the small bleeding resistor (color coded: Red-red-green-brown: 2.25KΩ) draws.
The components that are in parallel to the LED are:
1. A rather beefy (for the size) capacitor of a value between 0.47 .. 2.2μF to make the LED light smoothly (and not flicker due to the AC drive), and
2. A bleeding resistor of 2K25 to discharge the capacitor quickly when the power is removed, in order to prevent the LED from fading out.
-George