this was unlocked by my 10 year old nephew by completing the whole game
it features all missions with AAA rank and all grand prix cups won at first place at all difficulties
and you have a lot of SEGA miles and all SEGA shop items are already bought for you
didn't bother with time trial though
i don't know if this is the right place to upload it as I don't know how to upload to GCW.
hope you enjoy this
PS: trainer by cheatscape works only in rival battles and causes the game to crash (tested on many PCs, various OS, ran as administrator, all the instructions at their site).