Bug report 1.2.0 - Fixture Builder

HI there,

I've been attempting to create a fixture library for some CHinese searchlights on both the Full boar 4 and on hog4pc
Both are running 1.2.0

Upon hitting build fixture on the Full boar, the desktop crashes. I have tried this half a dozen times with the same result
Attepting the same procedure on Hog 4 PC (also 1.2.0) gives me an error message after hitting build fixture, screen shot attached


Gordo