Example not working

[labmaster]

I pulled https://github.com/thelsing/knx/tree/master/examples/knx-demo-diy and built it (PlatformIO) without errors.

Uploaded it to a ESP32 (NodeMCU ESP32) that has been connected to a MicroBCU (NCN5120) on Uart2 (Serial2 / GPIO16 and GPIO17) Additional i hooked up a LED (with Current lim. Resistor) and a Button (with Pullup) to GPIO18 (LED) and GPIO19 (BUTTON)

When i reset the System i get the following:

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0030,len:4604
ho 0 tail 12 room 4
load:0x40078000,len:15468
load:0x40080400,len:4
ho 8 tail 4 room 4
load:0x40080404,len:3180
entry 0x400805b8
readMemory
RESTORED FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF 
DataObject api changed, any data stored in flash is invalid.
expexted DataObject api version: 1, stored api version: FFFF
ETS has to reprogram PA and application!
TP is disconnected

When i press the button the LED toggles on/off and i get "progmode on" and "progmode off" in the serial (Serial1) monitor.

But the system does not connect to the KNX Bus. I already hooked up a logic analyzer (to RXd and TXD) and can see the MicroBCU (NCN5120) sending Data (19200, 8E1) to the ESP GPIO16 but the ESP32 does nothing on the TXD Pin.

In the Example the only parts that i change are the Button/LED definitions. Should there be anything additional changed... / added... that is not documented there ?

I'am a bit lost now how to go further.