Shadows in Unreal for OSX not showing correctly

I have copied a project from Windows to my Macbook Pro. It's the first time I try Unreal for OSX. In Windows everything worked perfectly, but in Mac shadows are showing like this:

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Building lights does not solve the problem and I don't know what to do.

( I don't know if it's relevant or not, but the second time I opened the project, Unreal started compiling gradients and crashed at the end. )

I've realize that those shadows are generated by Point Lights, because Focus Lights generate the shadows correctly.

I've tried these lights in a new project with a template created in this Mac and firstly they don't show correctly, but once I build the lights, they are okay:

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And I tried in another project taken from my Windows PC and I even can't build the lights because somethings get crazy and Unreal crashes, as you can see in this video:

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So maybe the problem is related to the operative system or I don't know...

Thank you again!

EDIT: It only happens when "Cast shadows" is marked. But in Windows it was also marked and it was not happening.