I'm at discovering KStars 2.7.9 with the built-in Simulators profile.
I selected Tarazed, slew to it, Preview, Auto focus complete.
Then I tried to Capture & Solve : it worked Online but repeatedly failed Offline.
I downloaded the whole 2Mass Catalog (31 GB of data !) with Astrometry of CloudMakers.
What am I doing wrong ?

Here are the logs for the Online success and the Offline failure :
2017-07-17T19:40:35 Solver failed. Try again.
2017-07-17T19:40:35 Starting solver...
2017-07-17T19:40:35 Solver iteration #1
2017-07-17T19:40:35 Image received.
2017-07-17T19:40:33 Capturing image...
2017-07-17T19:40:11 Target is within acceptable range. Astrometric solver is successful.
2017-07-17T19:40:11 Target is within 0° 00' 04" degrees of solution coordinates.
2017-07-17T19:40:11 Solution coordinates: RA (19h 47m 05s) DEC ( 10° 39' 30") Telescope Coordinates: RA (19h 47m 05s) DEC ( 10° 39' 27")
2017-07-17T19:40:11 Solver completed in 48 seconds.
2017-07-17T19:39:29 Upload complete. Waiting for astrometry.net solver to complete...
2017-07-17T19:39:23 Uploading file...
2017-07-17T19:39:23 Solver iteration #1
2017-07-17T19:39:23 Image received.
2017-07-17T19:39:21 Capturing image...

Turn Verbose on in Options to find what's going on.

I clicked on Options > Advanced > Verbose and run the autofocus again.
Here is the log:
2017-07-17T22:58:55 Autofocus failed, moving back to initial focus position 27000.
2017-07-17T22:58:55 Maximum travel limit reached. Autofocus aborted.
2017-07-17T22:58:55 FITS received. HFR 2.02 @ 28000. Delta (46%)
2017-07-17T22:58:55 Image received.
2017-07-17T22:58:52 Capturing image...
2017-07-17T22:58:52 Focusing outward...
2017-07-17T22:58:52 FITS received. HFR 2.48 @ 27000. Delta (44.6%)
2017-07-17T22:58:52 Image received.
2017-07-17T22:58:49 Capturing image...
2017-07-17T22:58:49 Please wait until image capture is complete...

We're talking autofocus or alignment?

EDIT: For autofocus, change maximum travel for Simulators to something like 50000 and you should be OK.

Beautiful. Thank you.

2017-07-17T23:10:28 Autofocus complete after 8 iterations.
2017-07-17T23:10:28 FITS received. HFR 1.63 @ 37782. Delta (0.321%)
2017-07-17T23:10:28 Image received.

Hi Jasem,
All this was my fault because I didn't install astrometry.net as described in "KStars for Mac Quick Start Guide"
Plate solving Offline works now beautifully.
Regards,