DASHBOARD apps menu problem on EX2ULTRA OS 3

Ι borrowed my son’s EX2ULTRA with 2.40.155 firmware (I have asked him to delay from upgrading to 2…40.157 and consequently to OS 5 later, as I did with mine EX2ULTRA).

OS 3 DASHBOARD apps menu shows NO APPS AVAILABLE on top and on the left there is a list of intalled apps, that cannot removed because there is not such an option.
Any idea to solve it is welcome.