Multimaker 3 printing very thin 1st layer. Problem in part of the initial print 1.0

Hi, I am a new user to 3D printing but I have had a reasonable amount of experience with CAD drawing. I am using Sketchup 7 Pro at the moment.

I created my own designed 2 sided thin poker chip with a round recess in the middle of it so I can place a round magnet in the centre. I can then attach it to a metal object with a recessed magnet inside the chip.

My problem is, that the first print layer prints very well in CURA 2.4, considering I set it to 0.02mm Layer Height and Top/Bottom Thickness 0.02. But the recessed hole does not print even though the recessed hole doesn't start until the print level is at 0.24mm from the base.

I am printing with 2 colours Black PLA and RED PLA with a 0.4 Print head.

The rest of the model prints fine even with the started 0.02 thin layer.

FILES and images are here:

Please Help if you can. :-)