Package errors with Paper2D to Win/HTML5 - 4.18

Hello all. I’m quite a novice and am trying to get acquainted with the UE engine by making a 2D platformer type game. I’m using the Paper2D module to work with sprites and flipbooks and have had moderate success so far. The game runs fine in editor or standalone, but will not package completely into an executable.

I get several of these warnings when trying to package:

UATHelper: Packaging (Windows (64-bit)):   F:\programs\UE_4.18\Engine\Plugins\2D\Paper2D\Source\Paper2D\Classes/PaperSpriteBlueprintLibrary.h(11): note: see declaration of 'UPaperSprite'
UATHelper: Packaging (Windows (64-bit)):   F:\users\drew\unreal projects\PFormer\Source\PFormer\PFormerHUD.cpp(150): error C2039: 'GetSourceSize': is not a member of 'UPaperSprite'
UATHelper: Packaging (Windows (64-bit)):   F:\programs\UE_4.18\Engine\Plugins\2D\Paper2D\Source\Paper2D\Classes/PaperSpriteBlueprintLibrary.h(11): note: see declaration of 'UPaperSprite'
UATHelper: Packaging (Windows (64-bit)):   F:\users\drew\unreal projects\PFormer\Source\PFormer\PFormerHUD.cpp(151): error C2039: 'GetSourceSize': is not a member of 'UPaperSprite'
UATHelper: Packaging (Windows (64-bit)):   F:\programs\UE_4.18\Engine\Plugins\2D\Paper2D\Source\Paper2D\Classes/PaperSpriteBlueprintLibrary.h(11): note: see declaration of 'UPaperSprite'

However these functions all do exist in PaperSprite.h and function as expected when running the game in editor. I’ve added the Paper2D module to my game.Build.cs file and don’t have issues outside of this packaging scenario. Is there something that I’m missing?