'launch path not " exception on OSX commit 183608046d0124eb9c97b0a7a023d909f9d26f71
The problem is that certain binaries in the required dependencies (that you download from GitHub, ahead of building) don't have execute permissions set. You can fix this by opening up Terminal.app and doing the following:
Change to the directory where you cloned the source repository. Mine is in /Users/myname/UnrealEngine
Change to the binaries directory and set perms.
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