Subtractive object causes a blank space.How do I remove it
This is a known issue reported with ticket UE-12157. Unfortunately it is backlogged and likely won't be addressed soon.
You can workaround this issue by setting up everything the way you like and then converting the BSP to a static mesh. The hole you're seeing will no longer be present. It's recommended to use Static Mesh over BSP as it is simply used for quick prototyping.
answered Jun 09 '15 at 05:35 PM
Tim Hobson ♦♦ STAFF
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