Ok hopefully found the final issue(s) (typo's and missed creating a myReminder Object

' Class Module cmADI_TMR
Option Explicit
Public WithEvents myReminders As Outlook.Reminders

Private Sub Class_Initialize()
    Debug.Print Now; "Init"
    Set myReminders = Outlook.Reminders
End Sub

Private Sub myReminders_BeforeReminderShow(Cancel As Boolean)
    If myReminders.Item(1).Caption = "ADI_TMR" Then
         Debug.Print Now; " b4 … calling exec code"
         Call ThisOutlookSession.tstCode
         myReminders.Item(1).Snooze (1)
         Debug.Print Now; " snz "; myReminders.Item(1).NextReminderDate
         Cancel = False ' default value
    End If
End Sub