HyperPixel 4.0 I2C doesn't work

Hi, i have a Hyperpixel 4.0 Rectangular Screen, which works fine, if i use it on all 40 Pins on my Raspberry. But if i wire the Screen over the 5 i2c pins, which are broken out, the Screen doesnt, even show a backlight. So my question: what am I doing wrong? I think if i wire the 3V3 and the GND Pin to the screen, there must be a light, which inidicates, that the screen is doing something, right?

This is why the Hyperpixel has an additional i2c break out on it. It uses all the Pins for DPI at Raspberry Pi GPIO Pinout

From the notes

HyperPixel uses basically all of the GPIO pins to communicate with the Pi (including the standard I2C pins) so it’s not generally possible to use it with other HATs and devices that connect via the GPIO…

so, is there no way to interact with any other sensor or actor at the same time??

Using the alternate I2C interface on HyperPixel 4.0 (for advanced users)
Scroll down the page some to find the instructions.
Getting Started with HyperPixel 4.0 (pimoroni.com)