Components disappearing

We are currently running a workshop and using glyphs, and all members had the same problem of created components disappearing.

Even if the file was saved or the programme was quit and restarted the glyph where the component was used mentions that the Base glyph is not found.

What version of Glyphs did you use?
Can you send me one of the .glyphs files?

One of the versions is 1.4.5 (612), another one is 1.4.3(584), another 1.4.4(611), another 1.4.4 (611).

The file I sent to info at glyphsapp is from version 1.3.25(526).