Crash / Vanish of app when importing XML

R15b2
OSX 10.13.4 release + security update
I try to import FCP 7 XML ( from prem pro ) and the app crashes / vanishes instantly after selecting the file and hitting ok. No import options dialog. File can be imported ok into 14.3
Same for FCP X 10.4.2 XML. R14 at least says it doesn't support X XML past ver 1.5 I think, I exported Ver 1.8. no option to export 1.5 from FCPX 10.4.2
S
OSX 10.13.4 release + security update
I try to import FCP 7 XML ( from prem pro ) and the app crashes / vanishes instantly after selecting the file and hitting ok. No import options dialog. File can be imported ok into 14.3
Same for FCP X 10.4.2 XML. R14 at least says it doesn't support X XML past ver 1.5 I think, I exported Ver 1.8. no option to export 1.5 from FCPX 10.4.2
S