UE4 packages everything in the project folder by default.

Specify only the maps you care about in DefaultEditior.ini

  • UE will then package everything referenced within those files

  • Note: Unused references are included (default texutres referenced in Materials or isolated blueprint nodes referencing assets). Be sure to clean up your graphs to minimize package size

To build for 64-bit release:

Change this in the source code:

Unfortunately there's no way of switching from the editor UI in the 4.2 build. If you want to change it manually,you can go to FMainFrameActionCallbacks::PackageProject() in Engine\Source\Editor\MainFrame\Private\Frame\MainFrameActions.cpp, and change this bit of code:

if (PlatformName == "WindowsNoEditor")
if (PackagingSettings->BuildConfiguration == PPBC_Shipping)
OptionalParams += TEXT(" -targetplatform=Win32");
OptionalParams += TEXT(" -targetplatform=Win64");

If you get rid of the check for the shipping configuration, it should work.

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