Crash in FMacApplication::FindScreenByCocoaPosition when using the mouse in the ILIAD plugin.

I think this could occur anytime but is probably very rare. However using this plugin from the reported UDN makes it much easier to repro as they are calling FMacApplication::ConvertCocoaPositionToSlate() on a non-game thread.

See more info at:

[Link Removed]

• Install and enable the IILAD plugin
• Create a texture asset
• Selected Edit with ILIAD
• Use the ILIAD window editor.
• Observe crash due to non thread safe use of TSharedRef<FMacScreen>.

"Get closest point on collision" does not work properly with PHYSICAL bodies