There is only one patch and it is for either but it seems to work best with 3.08. No harm to try that. Put it on a Fat 32 formatted USB. Insert it in the vehicle's slot with vehicle running. Bring up the display screen and then the file on the USB and activate it with you finger tap on the screen. I'm in North America so I'm not absolutely sure about the European needs. It seems that they are the same, but you might want to aski Riochim and he's in Europe - I believe.
The only way to reinstall Sync 2 Version 3.08 is to up grade it to version 3.10 before you go back to ver. 3.10. While in 3.10 you can install Riochim's Navupdate file for 3.10 and try to enable Navigation there - it's been done by others. If not then you can go back to 3.08 with the correct autoinstall.lst file and the Euro 3.08 file. Copy all of the following lines exactly for the Back to Euro 3.08 Autoinstall.lst file:
;+++++++++++++++++++++++++++++++++++++++++++++++
; Microsoft Windows Automotive
; USB Installation Directive File
; 3.8 (15128) Update from:
; 10308,10337,11038,11063,11081,11134
; 12023,12047,12058,12156,12285,13164,
; 13171, 13213, 13249, 13269, 13283, 13284, 13309, 13312
; 14073, 14122, 15042, 15050, 15085, 15091, 15109
; Other versions not supported
; autoinstall.lst (EU-Lang pack3 DE-DE_EN-GB_FR-FR_IT-IT)
;
;+++++++++++++++++++++++++++++++++++++++++++++++
;;;
;;; The following tags are software versions supported by this update
;;;
[SYNCGen2_4.23.11038]
[SYNCGen2_4.23.11063]
[SYNCGen2_4.23.11081]
[SYNCGen2_4.23.11134]
[SYNCGen2_4.26.12023]
[SYNCGen2_4.28.12156]
[SYNCGen2_4.29.12285]
Item1 = BT4T-14D546-EE
Open1 = SyncMyRide\BT4T-14D546-EE.cab
Item2 = EA5T-14D546-AKB
Open2 = SyncMyRide\EA5T-14D546-AKB.cab
Item3 = EA5T-14D546-HB
Open3 = SyncMyRide\EA5T-14D546-HB.cab
Item4 = EA5T-14D546-ACB
Open4 = SyncMyRide\EA5T-14D546-ACB.zip
Item5 = BT4T-14D546-FB
Open5 = SyncMyRide\BT4T-14D546-FB.cab
Item6 = EA5T-14D546-AHB
Open6 = SyncMyRide\EA5T-14D546-AHB.cab
Item7 = EA5T-14D546-ADB
Open7 = SyncMyRide\EA5T-14D546-ADB.cab
Item8 = EA5T-14D546-AEB
Open8 = SyncMyRide\EA5T-14D546-AEB.cab
Options = AutoInstall
;;;
;;; The following are the 3.08.15128 image files
;;;
[SYNCGen2_3.08.15128]
Item1 = EA5T-14D546-AFB
Open1 = SyncMyRide\EA5T-14D546-AFB.cab
Item2 = EA5T-14F496-MA
Open2 = SyncMyRide\EA5T-14F496-MA.zip
Item3 = EA5T-14F657-AE
Open3 = SyncMyRide\EA5T-14F657-AE.zip
Item4 = EA5T-14F497-DE
Open4 = SyncMyRide\EA5T-14F497-DE.zip
Item5 = EA5T-14D546-DE
Open5 = SyncMyRide\EA5T-14D546-DE.zip
Item6 = EA5T-14D546-FD
Open6 = SyncMyRide\EA5T-14D546-FD.zip
Item7 = EA5T-14F496-PA
Open7 = SyncMyRide\EA5T-14F496-PA.zip
Item8 = EA5T-14F496-RA
Open8 = SyncMyRide\EA5T-14F496-RA.zip
Item9 = EA5T-14F496-SA
Open9 = SyncMyRide\EA5T-14F496-SA.zip
Item10 = EA5T-14F496-UA
Open10 = SyncMyRide\EA5T-14F496-UA.zip
Item11 = EA5T-14F496-TB
Open11 = SyncMyRide\EA5T-14F496-TB.zip
Item12 = EA5T-14D546-AJB
Open12 = SyncMyRide\EA5T-14D546-AJB.cab
Item13 = EA5T-14F496-VD
Open13 = SyncMyRide\EA5T-14F496-VD.zip
Item14 = EA5T-14D546-AYD
Open14 = SyncMyRide\EA5T-14D546-AYD.zip
Item15 = EA5T-14D546-AGB
Open15 = SyncMyRide\EA5T-14D546-AGB.cab
Item16 = BT4T-14D546-EE
Open16 = SyncMyRide\BT4T-14D546-EE.cab
Item17 = EA5T-14D546-LB
Open17 = SyncMyRide\EA5T-14D546-LB.cab
Options = AutoInstall
;;;
;;; This tag runs only on Zodiac pre-release tags
;;;
[SYNCGen2_4.30.13171]
[SYNCGen2_4.32.14073]
[SYNCGen2_4.32.14122]
[SYNCGen2_3.08.15042]
[SYNCGen2_3.08.15050]
[SYNCGen2_3.08.15085]
[SYNCGen2_3.08.15091]
[SYNCGen2_3.08.15109]
[SYNCGen2_3.10.16180]
Item1 = BT4T-14D546-EE
Open1 = SyncMyRide\BT4T-14D546-EE.cab
Item2 = EA5T-14D546-AKB
Open2 = SyncMyRide\EA5T-14D546-AKB.cab
Item3 = EA5T-14D546-HB
Open3 = SyncMyRide\EA5T-14D546-HB.cab
Item4 = BT4T-14D546-FB
Open4 = SyncMyRide\BT4T-14D546-FB.cab
Item5 = EA5T-14D546-AHB
Open5 = SyncMyRide\EA5T-14D546-AHB.cab
Item6 = EA5T-14D546-ADB
Open6 = SyncMyRide\EA5T-14D546-ADB.cab
Item7 = EA5T-14D546-AEB
Open7 = SyncMyRide\EA5T-14D546-AEB.cab
Options = AutoInstall
;;;
;;; This tag runs only if none of the other tags match
;;;
[SYNCGen2_All]
Item1 = BT4T-14D546-EE
Open1 = SyncMyRide\BT4T-14D546-EE.cab
Item2 = EA5T-14D546-NB
Open2 = SyncMyRide\EA5T-14D546-NB.cab
Options = AutoInstall