How to compile engine from project solution

Hello. I am very new still to fiddling with the cpp code for UE4. Currently, I made some changes to the Steamworks Leaderboard cpp file UE4 Tips: Online Leaderboards | Shooter Tutorial and I want to compile so that it will keep the highest score rather than adding the new score to the previous value.

After the changes, I right click UE4 on the solution explorer and press build. Very fast, it says 1 succeded. However, when I relaunch the uproject, package, and test the new steamworks. It still has the old behaviour.

If I try to right click on ue4, then go to debug>start new instance, I get an error.

http://puu.sh/s4mk2/54d87849dd.png

So, I think that something is wrong then. I tried to follow this guide, but I am stucked.

Thanks

I think it’s related to this, But the answer doesn’t explain how to solve that. UE4 (Engine) project won't build - AnswerHub - Unreal Engine Forums

Hey -

If you are using the Launcher version of the engine then making changes to the engine source code will not be possible as the Launcher uses pre-built binaries. If you would like to change the source code you can download and compile the engine manually from GitHub (GitHub - EpicGames/Signup: Information about signing up for a free Epic Games account, and getting access to UnrealEngine source code. ) and then make changes as you see fit.

Cheers

Thanks! I managed to download and compile the engine, but I am having trouble adding a plugin that my project uses, before I merge my project to the new self-compiled engine.