@janek123 (View Post)
Everyone has given perfectly valid advice so far, you just don't understand it.

What mod are you trying to load? Maybe that will help. If you tell us the specific mod you want, someone can give specific instructions on how to load it.

There are two different types of mods, so depending on which type of mod it is, the instructions are entirely different.

The terminology here got a bit funky in the past few years, let me clear it up a bit. There are two ways to change how The Powder Toy works: you can either make a mod or write a script.

 

Mods are written in C++ and (may) fundamentally change TPT, which is an open-source project, meaning anyone can take the code, change it here and there, compile it and bug Mrprocom to add the result to the list of mods and jacob1 to host them on his server. These are basically different, standalone incarnations of TPT that you download separately as an executable. Each of these should have its own directory with its own saves and other stuff as mods are not guaranteed to not interfere with one another. As these are standalone, you can't combine them (unless by taking their code and merging them, which is not an easy task).

 

Scripts are written in Lua and are not standalone; they require a TPT executable to run them, which does not necessarily have to be the official one, but it usually is. You can get them by first installing the script manager and then opening that in-game and downloading scripts from there. These tend to extend the functionality of TPT rather than change it completely, mostly adding new elements or HUD elements. These you can usually combine, though exceptions exist.

 

The first list of mods lags behind a bit so the Realistic Physics mod is not up there yet, but the other one already has it: this is probably what you need. Just treat is as you treat the official TPT executable when you download it from the main page.