Change of the catalog index format. An index record was previously pointing directly to the RA,DEC coordinates.
Now the index point to a catalog record. This allow to process the stars proper motion for a correct location at any epoch. This also help to display the object label and full detail even if it is not visible with the current chart setting.
Because of this change you need to reinstall the Stars and DSO additional catalog.
This also upgrade the WDS, GCVS, PGC catalog to the latest 2012 version.
If you make you own catalog with Catgen you can rebuild your catalog to take advantage of the change but the old index still work as before.

• New Hammer-Aitoff projection.
• Option to not set the cylindrical projection equator to the chart center.
• Rotate the label of the planet simulation perpendicular to the orbit.
• Reduced label overlap (Display/Labels/Automatically optimize the labels placement).
• Add the component name to the label of double stars.
• Add Portuguese constellation names by Hugo D. Valentim
• Add Swedish translation by Kåre Lekebjer
• New option –userdir=
• Configuration file now use relative path when possible
• Add Thai translation by Worachate Boonplod
• Replace Etc/GMT timezone by the more intuitive UTC (GMT+5 → UTC-5)
• New 180deg rotation button.
• Meta+rotate button rotate by 180 degrees.
• Right click on rotate button reset the rotation to 0.
• Setup/Display “Show only text in detail window”, use if you have problem with the standard detail window.

• Fix Catgen Text catalog (need to rebuild text catalog done with 3.6)
• More reactive scrollbar
• Crash in planet computation.
• Accept command if running with –daemon option
• Wrong position when searching for planet name.
• Crash in Observatory database.
• Fix Setup/Pictures menu
• Fix UTF-8 picture path

For more details about the change you can look at the bug tracker change log and at the source code log