Succeed! I have downloaded navcore v9.541 SE by Tonyzeta (link in the 1st post) to TT One XL T 4S00.000 on 2GB SD card together with the map 1025.9386 and used latest Fastactivate to patch the navcore and the map. Unfortunately I face the same problem as Jakke and DigitalX - navcore didn't solve the GPS week number rollover problem - I still see time 0:00 even if set it manually it is overwritten by "wrong" GPS time :-((

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