Also, I would like to use this opportunity to thank Siberian Tiger from DTD Team for helping me with SVN builds for more than two years. You made my constant wrestling with the code a much less tedious process.
Game Configurations: changed default map name for Doom maps to "E1M1".
New Map Form: "E1M1" is now used as a default name for Doom maps.
Thing Browser Control: double-click event is now sent only if user clicked in the node's label area.
Interface: added info messages for several toolbar toggles.
Interface: made Brightness icon more readable when using dark windows themes.
Internal: UDMF sector slopes and offsets are no longer stored in sector.Fields. Use sector.FloorSlope, sector.FloorSlopeOffset, sector.CeilingSlope and sector.CeilingSlopeOffset.
Tag Range plugin: tags can be set in relative mode (when this mode is enabled, generated values are added to existing tags instead of replacing them).
Updated documentation.
Sectors mode: changed Alt-key handling. Now it only enables "snap to grid increment" mode.
Things mode: "snap to grid increment" mode now works in this mode.
Updated documentation.
Visual mode: real floor was colored by 3d floor's color even when it was below real floor.
Action Browser form: keyboard focus is now set to Filter text box by default.
"Texture 'XXX' is double defined in resource 'YYY'." warning is no longer displayed if a TEXTURE1/2 texture contains a patch with the same name as the texture.
Script names/numbers cache was not updated (no scripts were shown in the drop downs when using script setting actions).
SCRIPTS lump was not saved when saving a map.
BCC script compiler (https://github.com/wormt/bcc/) is now bundled with GZDB.
Main Form, "File" menu: only existing files are now added to the "recent files" list.
Linedefs Mode: "Flip Linedefs" action now tries to align linedefs, so their front (or back) point towards the same sector.
Sectors Mode: "Flip Linedefs" action is now available form this mode, and it will also try to align linedefs, so their front (or back) point towards the same sector.
Preferences: added "Capitalize texture names" option (located in Preferences -> Appearance -> Additional options). When disabled, the casing of displayed texture names will match filenames for textures loaded form TEXTURES or pk3/pk7/folder resources.
Textures Browser: added support for displaying long texture names.
Errors list is now cleared when reloading resources.
Visual mode: added basic support for sector slopes (no UI for that feature yet).
Snippets: changed token syntax from $XX to [XX]
[LB] (Line Break) marker can now be used in snippets.
Game Configurations: added "enabledbydefault" parameter. When set to true, a game configuration will be available by default (e.g. when an user starts the editor for the first time).
GZDB will no longer throw an exception when trying to update default value in a TypeHandler, which doesn't implement default value handling.
Script Editor: added snippets to auto-complete list (currently they aren't inserted properly though...).
Script Editor: auto-indentation now works a bit smarter.
ScintillaControl.GetLine() was retrieving incorrect line.
Randomize mode: randomized pitch, roll and scale can now be applied to things.
Randomize mode: removed "Relative" option, because results with this option enabled were almost the same as without it.
Classic modes, model rendering: selected models are now rendered using highlight color, so they no longer blend with thing rectangle/circle.
Model rendering, UDMF: scale was applied incorrectly to models with pitch or roll.
Updated documentation.
Thing Edit form, UDMF: default value of pitch and roll angle controls is now up.
Angle control: direction line is not displayed when showing mixed values.
Thing Edit Form, UDMF: added controls for setting pitch, roll, scale, render style, fill color, alpha, health and score.
Visual mode, UDMF: UDMF scale is now applied when rendering sprites.
Added Thing Statistics form (Edit -> View Thing Types...), which shows all loaded thing types with some additional info.
Visual mode: sprites with negative ScaleX and positive ScaleY were not rendered properly.
Classic modes: display was not updated after loading a sprite.
Current testing engine change was not saved on closing the program when no other game configuration settings were changed.
Moved "Rotate Clockwise" and "Rotate Counterclockwise" actions to "Edit" category.
Tag Statistics form: help label was incorrectly aligned.
Some actions in Sectors and Linedefs modes were not used on highlighted map elements.
Some actions in Sectors and Linedefs modes created undo groups incorrectly when used on highlighted map elements.
"Preferences -> Editing -> When splitting a linedef" setting is now always used when splitting linedefs.
"Preferences -> Editing -> When splitting a linedef": added "Reset X and Y" option.
"Preferences -> Editing -> Auto-align textures of newly created linedefs" option now works in a more intelligent fashion.
GLDEFS parser: added a warning when the interval of animated dynamic light is 0.
Visual mode: fixed a crash when an angle of animated dynamic light was set to 0 and light animation was enabled.
Tag explorer: removed unnecessary mode switching when selecting map elements of the same type.
Make Door action: door and track textures are now stored while the editor is running.
Edit Selection Mode: pasted geometry was not merged with the rest of the map if the selection was not modified before applying the mode.
Make Door action: made Make Door form a bit smaller.
Make Door action: sector highlight was not updated after performing the action when a single sector was selected.
Error Checker mode: added "Check missing flats" check.
Error Checker mode: fixed several descriptions.
Sprite patches for sprites defined in TEXTURES are now loaded from Sprites namespace.
Some of my older texture alignment code didn't work properly when strict texture/flat handling ("mixtextureflats" game configuration flag set to false) was enabled.
Fixed some incorrect checks for missing texture ("-").
Fixed a crash when using "Reload GLDEFS" and "Reload (Z)MAPINFO" actions when GLDEFS / MAPINFO file was moved or renamed after opening the map in the editor.