A funny thing... I used the brick substitution fix method to replace the bricks of Astrok Outline with solid Connect blocks. There were the odd custom bricks I had to solve for. But after I did that Preview was still showing some old bricks in the fonts (making holes in the glyph) that I could not see. But after exiting the Fontstructor, everything was reset and it all seems to work.

When I moved the brick from within the glyph and put it back, the Preview function would update the glyph in Preview, though. Just an easy to fix anomaly in the Preview.

Alrighty, then. I noticed a stray brick on the top terminal of the c, then the s, soon I found them scattered throughout the font.  I cleaned it up and tried to patch the hole I see in the 4 in Preview mode, but I do not find anything wrong with it.  I checked everything twice for stray bricks and saved it an extra time.  I only have this one web Fontstruct browser window open (using Chrome on Windows 10 Pro), but the last Windows Update DID introduce some File Explorer bugs (and that is why I am on Chrome, because the FileExplorer bug killed @FireFox and @MicrosoftEdge). 

So, I have my fingers crossed.  It was OK when I left the Fontstructor.