I am using the Serious Astronomer version 10.5.0 (Build 12165). I did update to build 12463.
My FOV have disappeared. Ctrl+F6 reveals they are valid. They were there yesterday and I have not made any system wide changes or updated the Win10 OS.
The following is the content of the 'My Equipment' file in the Documents directory:
;Copyright (c) Software Bisque 1984-2012 http://www.bisque.com
;Equipment file version 1.100
;Field 1: [T]=Telescope, [E]=Eyepiece, [D]=Detector, [F]=Field of view indicator
;
;My Telescopes
;-----------------------------------------
[T]|1|Celestron C11 f/10 SCT| 280.000| 10.000|
;
;My Eyepieces
;-----------------------------------------
[E]|1|Celestron 23 mm Lumnos Eyepiece 2"| 23.0| 82.0|
;
;My Detectors
;-----------------------------------------
[D]|1|Nikon D5300|mm|Rectangle|CCD|23.500|15.600| 6000| 4000|0.000|0.000|
;
;My FOVIs
;-----------------------------------------
[F]|1|2|Celestron C11 f/10 SCT + Celestron 23 mm Lumnos Eyepiece 2"| 0.0|0.00|0.00| 121.7391|0|Eyepiece|am|Circle|Eyepiece|40.414|40.414| 0| 0|0.000|0.000|0|0|
[F]|1|2|Celestron C11 f/10 SCT + Nikon D5300| 0.0|0.00|0.00| 0.2885|1|Nikon D5300|mm|Rectangle|CCD|28.852|19.153| 6000| 4000|0.000|0.000|0|0|
[F]|0|0|Celestron C11 f/10 SCT + Celestron 23 mm Lumnos Eyepiece 2"| 0.0|0.00|0.00| 121.7391|0|Eyepiece|am|Circle|Eyepiece|40.414|40.414| 0| 0|0.000|0.000|Marker|Center|0.000|0.000| 0| 0|0.000|0.000|0|0|