Very nice work! Maybe PHP-GTK is an option for you (standalone, can connect to sqlite, glade to "design" ui, ...)
To start a php-gtk-app you can use a litte c++ "wrapper" (to avoid the command line) like this:
#include <stdlib.h>
#include <windows.h>
int main() {
WinExec("php-gtk2\\php-win runwaySafetySystem.php",SW_SHOWNORMAL);
return 0;
}
Of course it's only an option if your app should be open source.
regards,