Version 1.9.4 was released in December 2021. It is a free upgrade via the Apple App Store for all existing users.
The alignment algorithm has been replaced. The new algorithm works much better with images that do not have many sharp stars to align. It is also much faster.
The limits on the values for white balance during RAW conversion have been broadened to support the use of light-pollution filters which require extreme white balance settings. If you are trying to copy temperature and tint values from Lightroom or Adobe Camera RAW, I find that I have to multiply the tint value from Lightroom by about 1.2 to get a good match in SLS. These numbers are arbitrary so I am not surprised that there is not much agreement between RAW converters.
Added the ability to process a single light frame, saving it after applying darks and flats.
Fixed some issues in the preferences. Sometimes white balance values were not saved properly. They are now. Also, now if the RAW conversion settings window is open when the preference are changed, the RAW conversion settings are updated to reflect the new preference settings.
Fixed a some UI issues with the image classification panel.