As you recommended, I have assigned through FSUIPC a command to open each of the doors, I assigned the command Ctrl + Shift + 2 for Toggle Aircraft Exit with parameter 2. I have done it with the parameter "TimeForSelect "configured for 4, unfortunately it has not worked. Here is the log:
Running inside Prepar3D v4 on Windows 10
Module base=7FF9D0EF0000
1265906 Ready Flags: Ready-To-Fly=Y, In Menu=N, In Dlg=N
1265906 READ0[8000] 3304, 4 bytes: 00 00 53 51 ..SQ
1265906 READ0[8000] 3308, 4 bytes: 0C 00 DE FA ....
1266000 READ0[8000] 330C, 2 bytes: 06 00 ..
1266656 KEYDOWN: VK=16, Waiting=0, Repeat=N, Shifts=1
1266656 .. Key not programmed -- passed on to FS
1266813 KEYDOWN: VK=69, Waiting=0, Repeat=N, Shifts=1
1266813 .. Key not programmed -- passed on to FS
1266813 *** EVENT: Cntrl= 66389 (0x00010355), Param= 0 (0x00000000) TOGGLE_AIRCRAFT_EXIT
1266813 *** EVENT: Cntrl= 66514 (0x000103d2), Param= 0 (0x00000000) ATC_MENU_CLOSE
1266813 *** EVENT: Cntrl= 66514 (0x000103d2), Param= 0 (0x00000000) ATC_MENU_CLOSE
1266969 KEYUP: VK=69, Waiting=0
1267000 KEYUP: VK=16, Waiting=0
1267125 KEYDOWN: VK=50, Waiting=0, Repeat=N, Shifts=0
1267125 .. Key not programmed -- passed on to FS
1267125 *** EVENT: Cntrl= 65539 (0x00010003), Param= 0 (0x00000000) SELECT_2
1267281 KEYUP: VK=50, Waiting=0
1272828 KEYDOWN: VK=16, Waiting=0, Repeat=N, Shifts=1
1272828 .. Key not programmed -- passed on to FS
1273031 KEYDOWN: VK=69, Waiting=0, Repeat=N, Shifts=1
1273031 .. Key not programmed -- passed on to FS
1273031 *** EVENT: Cntrl= 66389 (0x00010355), Param= 0 (0x00000000) TOGGLE_AIRCRAFT_EXIT
1273031 *** EVENT: Cntrl= 66514 (0x000103d2), Param= 0 (0x00000000) ATC_MENU_CLOSE
1273031 *** EVENT: Cntrl= 66514 (0x000103d2), Param= 0 (0x00000000) ATC_MENU_CLOSE
1273188 KEYUP: VK=69, Waiting=0
1273219 KEYUP: VK=16, Waiting=0
1273375 KEYDOWN: VK=50, Waiting=0, Repeat=N, Shifts=0
1273375 .. Key not programmed -- passed on to FS
1273375 *** EVENT: Cntrl= 65539 (0x00010003), Param= 0 (0x00000000) SELECT_2
1273485 KEYUP: VK=50, Waiting=0
1278422 KEYDOWN: VK=17, Waiting=0, Repeat=N, Shifts=2
1278422 .. Key not programmed -- passed on to FS
1278610 KEYDOWN: VK=16, Waiting=0, Repeat=N, Shifts=3
1278625 .. Key not programmed -- passed on to FS
1279047 KEYDOWN: VK=50, Waiting=0, Repeat=N, Shifts=3
1279047 FS Control Sent: Ctrl=66389, Param=2 TOGGLE_AIRCRAFT_EXIT
1279047 .. This key is programmed in FSUIPC5 'Keys' options
1279047 Exception 1 "ERROR", Ref 3387, Index param 2 on TransmitClientEvent, object=1, id=66389 (TOGGLE_AIRCRAFT_EXIT), data=2
1279266 KEYUP: VK=50, Waiting=0
1279344 KEYUP: VK=16, Waiting=0
1279344 KEYUP: VK=17, Waiting=0
1281031 KEYDOWN: VK=18, Waiting=0, Repeat=N, Shifts=4
1281031 .. Key not programmed -- passed on to FS
1281125 Deactivated for PID=2496, "explorer.exe"
1281141 Lost focus to PID=2496, "explorer.exe"