In Copper Zone Priorities dialog
Hover mouse over Priority level
Tooltip pops up with"If its priority is highter..."
Correct spelling to "higher"
I also suggest adding a line above "Level 2 is higher priority than Level 1" as this is not obvious.
See forum thread https://forum.kicad.info/t/copper-zone-in-copper-zone-is-not-allowed/6047
Application: kicad
Version: 4.0.6-e0-6349~53~ubuntu16.04.1 release build
wxWidgets: Version 3.0.2 (debug,wchar_t,compiler with C++ ABI 1009,GCC 5.4.0,wx containers,compatible with 2.8)
Platform: Linux 4.4.0-72-generic x86_64, 64 bit, Little endian, wxGTK
Boost version: 1.58.0
Curl version: libcurl/7.47.0 OpenSSL/1.0.2g zlib/1.2.8 libidn/1.32 librtmp/2.3
USE_WX_GRAPHICS_CONTEXT=OFF
USE_WX_OVERLAY=OFF
KICAD_SCRIPTING=ON
KICAD_SCRIPTING_MODULES=ON
KICAD_SCRIPTING_WXPYTHON=ON
USE_FP_LIB_TABLE=HARD_CODED_ON
BUILD_GITHUB_PLUGIN=ON
Looks like JP Charras fixed the "highter" in this commit 6 days ago:
https:/
Still leaves the confusion about whether 1 is the highest priority or the actual case "2 is higher than 1". Both conventions are common