Yestedray at late night finaly managed to work, to do this I deleted almost all code from ui.ino file, used Lilygo suplied libraries of lvgl, now code of ui.ino looks like this:

#include <LilyGo_RGBPanel.h>
#include <LV_Helper.h>
#include <TFT_eSPI.h>
#include <ui.h>

LilyGo_RGBPanel panel;

void setup()
{
Serial.begin(115200);

// Initialize T-RGB, if the initialization fails, false will be returned.
if (!panel.begin()) {
    while (1) {
        Serial.println("Error, failed to initialize T-RGB"); delay(1000);
    }
}

// Call lvgl initialization
beginLvglHelper(panel);


ui_init();

Serial.println( "Setup done" );
panel.setBrightness(16);    

}

void loop()
{
lv_timer_handler(); /* let the GUI do its work */
delay(5);
}

Later will make SLS template, thanks for advices ;-).

Yestedray at late night finaly managed to work, to do this I deleted almost all code from ui.ino file, used Lilygo suplied libraries of lvgl, now code of ui.ino looks like this:

#include <LilyGo_RGBPanel.h>
#include <LV_Helper.h>
#include <TFT_eSPI.h>
#include <ui.h>

LilyGo_RGBPanel panel;

void setup()
{
Serial.begin(115200);

// Initialize T-RGB, if the initialization fails, false will be returned.
if (!panel.begin()) {
    while (1) {
        Serial.println("Error, failed to initialize T-RGB"); delay(1000);
    }
}

// Call lvgl initialization
beginLvglHelper(panel);


ui_init();

Serial.println( "Setup done" );
panel.setBrightness(16);    

}

void loop()
{
lv_timer_handler(); /* let the GUI do its work */
delay(5);
}

Later will make SLS template, thanks for advices ;-).

Hello, I purchased wonderful round display 2,8" Lilygo T-RGB but can't make it work with SquareLine Studio Arduino, installed all libraries like said in Github page but nothing, compiles normaly, but no picture at all. Lilygo samples working, but when compiling SLS sketch nothing, maybe someone has made template for SLS that works with Lilygo T-RGB display?