I'm fairly new to all this. Can this work with games through GOG? I just bought the Mortal Kombat trilogy.

Thanks.

I have one of these.

It won't work with every game on GOG out of the box - but the same is true for all controllers. It is a versatile controller though and has multiple modes that should support all games on GOG that have controller support (it can do both xinput and directinput).

Games that do not have controller support will require external tools to map controller buttons to keyboard and mouse input. There are a lot of options for these but I personally use Xpadder.

I can't help with MK Trilogy as I don't have it, but if it doesn't have native controller support you should be able to map the controller to the keyboard.

Ah. I tried running Xpadder but it said I need a "more advanced" version of Windows, such as Vista. I'm running Windows 10, so I don't think I'm "less advanced".

Well that suggests you're running an old version of Xpadder that doesn't know what Windows 10 is. ;)

Please note, Xpadder is a commercial programme. If you didn't pay for it then it's probably an old pirated version.

That makes sense. I'll look into the paid (from this decade!) version. Is it plausible for a noob like me to get it working?

It's pretty user friendly but I'm sure there are some free alternatives. Maybe someone else will come along with some other suggestions?

DOSBox has a remapper; I had a little success, but it kept reading that I was pushing down somehow, keeping my character in a crouch, so I don't think I'm getting it right.

Ah yeah, I don't have any experience using that, sorry.

JoyToKey is a shareware alternative.
Another one is AntimMicro.

But I haven't used them though, so I can't tell you what they're worth.

Try antimicro. It's almost identical to Xpadder, except it's still in active development and is free.
https://sourceforge.net/projects/antimicro.mirror/

Another thing to not forget is the The Dosbox Keymapper, that while arcane, is very powerful.

Xpadder is in active development, although it's so damn stable I often forget to update. You might be thinking of Pinnacle, the developer of which unfortunately died.