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 ("-").
Visual mode: fixed a crash after disabling GZDoom rendering effects (Tab key) when visual sector was not created for sector with 3d floor's control linedef.