Attached please find a gerber file which doesn't import propery. The unfilled areas (I've highlighted them in red) at [6mm,19mm] and [24mm,19mm] should be fiilled just like all surrounding copper. The cam350 displays them correctly as well as gerbv (see attached screenshots).
FlatCAM version 8.1 on Ubuntu 14.04. The gerber file created in Pulsonix 8.0.