Hi giwrgos74
Main issue is due to the bootstrap css adding the display none to the class modal , this can be solved adding new rules to the custom.css file like i did
.modal {
display:inline!important;
position:relative!important;
}
But after this there is an issue with the jch optimize plugin if enabled then there is the issue , if i disable it as it is now then popup and link works fine as you can see
Also there is a conflict issue with below plugin which is now disabled, you can see the error enabling the error reports at maximum value from global configuration
Content - GMapFP
Conclusion , your page is now working
Regards