High-DPI: fixed alignment issues in Sector, Thing, Linedef and Vertex Edit Forms, also in Open Map Options and Map Options Forms.
Changed: Thing Browser Form is now resizeable.
Changed: made default Texture Browser Form size smalled, so it properly fits the screen when using low display resolution.

Linedef Edit Form (Doom/Hexen map formats): fixed incorrect window size when using low display resolution (like 1024x768).

DECORATE parser: added special handling for ZDoom's special sprite names (namely TNT1, "####" and "----").
Internal: changed the way apppath is acquired. It should no longer fail when launching the editor from a shared network folder.
Main Form: changed some labels of dynamic light and model rendering selectors to be less confusing.
Updated ZDoom_DECORATE.cfg.

Internal: moved TNT1A0 ignoring logic to a more adequate place (why these "proper implementation" ideas always occur right AFTER I commit stuff?..)

Updated ZDoom_DECORATE.cfg. 

High-DPI: added app.manifest, which enables application DPI-awareness.
High-DPI: ExceptionDialog is now displayed properly.

Apparently, we can no longer load a map named "MAP" after r2151. Let's warn a user about this unfortunate event.

Added more checks and fixed incorrect flag assignment in UDMF -> Hexen action conversion from r2155. 

Updated SharpCompress library from 0.8.1 to 0.10.3. This fixes inability to load certain PK7 files and grants a 2x performance boost when loading PK3 and PK7 files.

Added Hexen -> UDMF and UDMF -> Hexen action conversion as described in "Universal Doom Map Format ZDoom extensions" (udmf_zdoom.txt). It is used when changing map format form Hexen to UDMF and from UDMF to Hexen.
Game configurations, Line Identification action: added "Front side only" (128) flag to arg1.
Game configurations, Line Identification action: renamed arg1 flags to match corresponding UDMF flag names.
Updated udmf_zdoom.txt.

Fixed: PairedFloatControl had incorrect initial link icon.
Internal, AngleControl: rewritten AngleChanged event so it behaves like the rest of custom events.
Updated GZDB icon.

Find and Replace mode: only used sidedef parts are now found when searching for missing texture ("-").
Find and Replace mode: only textures on used sidedef parts are now replaced when replacing missing texture ("-"), 

Fixed, Fit Textures action: vertical texture offset of a middle part of double-sided linedef with "Lower unpegged" flag was calculated incorrectly.
Fixed, Fit Textures action: texture offsets were calculated incorrectly when using the action on several groups of connected walls at once with "Fit across connected surfaces" enabled.
Fixed, Visual mode: middle parts of double-sided linedefs were not rendered when ScaleY was negative.
Updated ZDoom_DECORATE.cfg.

Visual mode: "Fit Textures" action can now fit textures across multiple selected surfaces. A number of times to repeat a texture can now be specified.  
Visual mode: removed "Fit Texture's Width" and "Fit Texture's Height" actions.
Visual mode: "Auto-align texture offsets" actions were incorrectly aligning double-sided middle walls in some cases.
Visual mode: "Auto-align texture offsets" actions now align non-wrapped double-sided middle walls to vertical offset closest to their initial vertical offset.
Visual mode: middle parts of double-sided walls were ignored when Shift-selecting walls.
Nodebuilders/Game configurations: GL nodes definitions were missing from game configurations.
Nodebuilders/Game configurations: "~MAP" wildcard can now be a part of a lump name. 
Nodebuilders: GL nodes were not properly handled by the editor.
Main Window: the window is now moved into the view when stored position is ouside of screen bounds. 
Classic and Visual modes: changing thing pitch was ignored in some cases.
Visual mode: raising and lowering a thing with "+SPAWNCEILING" flag now works the same way as when raising/lowering a regular thing.
Visual mode: using "Raise/Lower Floor/Ceiling to adjacent sector" actions on a thing with "+SPAWNCEILING" flag now works the same way as when using them on a regular thing.  
Rendering: even more fixes to MODELDEF and UDMF properties-related model rendering logic.
Internal, ResourceListEditor: rewritten resource validation check in a more OOP-ish way.
Configurations: fixed an infinite loop crash when a file was trying to include() itself.
UDMF thing flags: added Skill 6-8 to the flags list (because there are thing filters for these).
ZDoom_ACS.cfg: added definitions for SetTeleFog and SwapTeleFog.
ZDoom_DECORATE.cfg: added definitions for A_SetTeleFog and A_SwapTeleFog.
Updated ZDoom ACC.
Updated documentation.

Resource List Editor: not existing resources are now shown using different color. 
Map Options, Open Map Options, Game Configurations windows: a warning is now shown when a map resource doesn't exist.
Some minor fixes to Resource List Editor's context menu.
Updated ZDoom_DECORATE.cfg.

Resource List Editor: fixed potential crash on pasting/replacing resources when there are duplicate resources in the list.
Resource List Editor: duplicate resources are no longer added when adding resources using drag and drop.

Resource List Editor now has a context menu.
Fixed misleading warning asking user to install DirectX when unable to detect SlimDX.

Rendering: mode fixes to MODELDEF and UDMF properties-related model rendering logic.

Fixed, Rendering: MODELDEF RollOffset, AngleOffset, Scale and ZOffset properties were applied incorrectly.
Fixed, Rendering: VOXELDEF Scale property was applied incorrectly.

Import Wavefront .obj as Terrain mode: floor height of each created sector is now set to the average height of an .obj polygon it was created from.
Import Wavefront .obj as Terrain Settings window: added "Use slopes" checkbox. When enabled, the mode will create slopes using vertex height offsets (UDMF) or Floor Vertex Height things (1504).
Fixed, Visual Mode: things were rendered at wrong height after using "Lower/Raise Height" actions in sectors with sloped floor (or ceiling for ceiling-aligned things) 
Fixed: info panel was not updated after switching to another Edit Mode.

Find and Replace window: added "Find Previous" button.

Script Editor: expanding snippet by pressing the Tab key now works only when the text cursor is at the end of a keyword.
Updated ZDoom ACC.
Updated ZDoom_things.cfg.
Updated documentation.

Bit Flags form now changes width to show flags with long names without scrolling.
Bit Flags form: flag numbers are now shown as well as names.
Game configurations: updated Hexen and ZDoom linedef definitions. Now they (hopefully) fully match ZDoom ones. 
Action Selector Control: fixed a crash when trying to increase action above maximum value using mouse wheel.
Sector/Linedef/Thing tag lists are now handled by corresponding TypeHandlers (and not by dirty hacks as before).
Linedef info panel: line peggedness labels were obscured by effect label in Doom/Hexen map formats.

Thing\Linedef Edit Form: added some tooltips.
Some cosmetic layout changes in LinedefEditForm.

Game configurations: removed some irrelevant info.

Cosmetic changes in Sector Info Panel and Thing Browser Control.
ArgumentInfo: fixed a crash when enum specified in a game configuration doesn't exist.
Updated Hexen and ZDoom linedef configs.
Updated ZDoom_DECORATE.cfg

Thing, Sector, Linedef edit forms, UDMF: fixed more cases when missing game configuration blocks crashed the forms.
Thing and Sector edit forms, UDMF: fixed some minor layout issues.

Fixed, Texture Browser form: we should not save "Long texture names" value when Map.Config.UseLongTextureNames is disabled.
Fixed, Linedef Edit form (UDMF): fixed a crash on opening the form when "linedefrenderstyles" block was missing from game configuration.

Texture Browser Control: "Long texture names" and "Show image size" values are now stored in program configuration.

Fixed, Texture Browser Form: well, I broke "Tab" key functionality again (in previous commit)...
Maintenance: changed curly braces style to match DB2 one (hopefully not breaking anything in the process...).
Maintenance: changed private method names casing to match DB2 one.

Texture browser form: added "Long texture names" check-box. It can be used to toggle between displaying long and short texture names.
Texture browser form: added "Show image size" check-box.
Texture browser form: image size is now shown differently.
Image Selector: added a button to toggle between long and short texture name.
Linedef info panel: long texture names are now displayed properly.
Sector info panel: long texture names are now displayed properly.
Fixed: "Save Screenshot" and "Save Edit Area Screenshot" actions were triggered multiple times when a child window was open.
Fixed: used textures should be always updated after using "Change map in current WAD" action.
Fixed, "Change map in current WAD": fixed a crash when trying to switch from a map with missing game configuration path.
Updated ZDoom_ACS.cfg.

Added long texture names support (enabled when "longtexturenames" game configuration property is set to true and "Use long texture names" check box is checked in Map Options).
Open Map in Current WAD: resources are now reloaded when current and target map's resources don't match.
Added some boilerplate to UniversalParser and PK3FileImage.
Internal: ImageSelectorControl now has "UsePreviews" property.
Internal: added ConfigurablePictureBox.
Updated ZDoom_DECORATE.cfg.

Game configurations: fixed "Door Generic (202)" movement speed, type and delay, fixed "Door Close Wait Open (249)" movement speed and delay.

Linedef Edit Form, UDMF: "Lock number" now has a drop-down with supported key types (no LOCKDEFS support (yet?)). You can still type lock number manually.