Slade crashing when I open the color remaper.

This is going to be difficult to troubleshoot, but we can try.

Version of SLADE, what OS are you using, anything looking odd in the console log?

This is the console log:

Windows Version: 6.1
SLADE - It's a Doom Editor
Version 3.1.6
Written by Simon Judd, 2008-2019
Compiled with wxWidgets 3.1.2 and SFML 2.5.1
--------------------------------
Loading configuration
Loading resources
Loading icons
Loading entry types
Loading text languages
Loading text style sets
Loading colour configuration
Loading base resource
Base resource loaded
Loading game configurations
Read game configuration "doom2" + "zdoom"
SLADE Initialisation OK
Checking for updates...
Latest stable release: v3.1.5
Latest beta release: v3.1.2 beta 5
Already up-to-date
Opening archive C:/Users/Sir Hattington/Desktop/GZDoom/DOOM2.WAD
Warning: No fluidsynth soundfont set, MIDI playback will not work
Opening took 957 ms
Initialising OpenGL...
OpenGL Version: 2.1
Max Texture Size: 4096x4096
Checking extensions...
Vertex Buffer Objects supported
Point Sprites supported
Framebuffer Objects not supported

I happen to have another problem with the color remapper.   Here's a screenshot of how I can't see the top portion of it.  My laptop is maxed at 1366x768 resolution. Fortunately, I can still accomplish what I want by loading translation string txt files of the series of colors to remap. 

When I press any of the buttons highlighted with red squares in this screenshot, it will crash Slade.

To access the color remapper, I highlight the series of entries by shift-clicking, then right click, Graphics, Colour Remap...

Assessing the color remapper through right clicking crashes Slade too.

The common trend here is that anything that opens a modal window causes a crash. Even closing SLADE opens one to ask you to confirm and whether you want to save changes first.

To check this hypothesis, open an archive that actually has texture definitions (you Doom IWAD will do), and then you should be able to use the texture editor as it'll open a tab instead of a modal window.

Another thing you can do to check is go to Edit->Preferences. It opens a modal window too. Same for Help->About or Tools->Script Manager.

1 hour ago, Gez said:

Another thing you can do to check is go to Edit->Preferences. It opens a modal window too. Same for Help->About or Tools->Script Manager. 

Doing those things don't seem to crash Slade.