RCT3 Gold and RCT3 Platinum - What's the difference between them?

I have RCT3 platinum, is that the latest version...it includes soaked and wild?

In the program file, it has RCTPlus is that a different program as well?

The difference between RCT3 Gold and RCT3 Platinum is that the Gold version contains only RCT3 and the Soaked! expansion pack. Platinum contains the RCT3, and both the Soaked! and Wild! expansion packs. And yes, RCT3 Platinum is the latest version.