invisible player, portals crash by existing, start dual crash, placing ◊ in practice mode crash:
0_0_0_-1_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0
no end wall glow:
0_0_-1_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0
both effects:
0_0_-1_-1_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0_0
put one of these <k>k67</k><s>here</s> in CCLocalLevels.dat (it's usually encoded)
I use https://gdccdated.glitch.me/index.xhtml for easier than text editor editing of CC*.dat files
playing (no need to finish or die) level in CCLocalLevels.dat (in create tab) will generate new <k>k67</k><s>extraString</s>
playing level in CCGameManager.dat (in saved tab) will not generate new <k>k67</k><s>extraString</s>