I fixed TDUPE issue by following "Q. TDUPE is not working?" under "[Released] Test Drive Unlimited Platinum" topic.
But as mentioned item number "1105" did not worked. When i opened "TDU_CarPhysicsData.db" of mine, there was "11100"... I just removed one zero to make it 4 digit number and game launched just fine with TDUPE edited data.
The interesting fact is that for example: I adjusted Maximum RPM using both TDUPE and TDUF, both works in Hardcore Mode... BUT, when i adjusted Steering Lock using both TDUPE and TDUF, none of them are capable of making changes in Hardcore Mode.
This drives me towards the conclusion that there is something going on with the way TDU Platinum is built, because inside vanilla TDU had no problems making changes in Hardcore Mode of the game.
Hopefully this is something that can be sorted out, it's great to see you guys create such lovely pieces of software.