Thanks to @xrubioj for pointing the his solution

This fix addresses the Blocked Plugin issue and UI properties are
usable than a blanked out UI from @xrubioj original PR
radiant-player#670

Legacy Build System is needed so i enabled it in my workspace

Only if you set `UseModernBuildSystem=NO` in the Workspace setting

```
Xcode 9.3 adds a new IDEWorkspaceChecks.plist file to a workspace’s
shared data, to store the state of necessary workspace checks.
Committing this file to source control will prevent unnecessary
rerunning of those checks for each user opening the workspace.
```

Word correction