@MortenMacFly : The nightly bulid works fine, but due to @ptDev, the nightly build has de_CH on the right corner, but my build has a plus sign instead of de_CH.
The default setting of de_CH has nothing to do with my patch. That is not the problem in itself.
de_CH has always been the default language selection of the SpellChecker (you can look up in SpellCheckerConfig::Load()). You get the cross (flag of Switzerland) in your local build, because that flag .png is included in the repository, and it gets copied to ... share\CodeBlocks\Spellchecker during the contrib plugins build.
The problem is caused by a missing check when populating and selecting the dropdown in the configuration page. de_CH is loaded to status bar field as the current string/selection (since it is a valid selection, because it is in the language map, but the language is not installed in the nightly build, nor in the unofficial installer build, no flag is shown there, and the string appears). Then, when the Editor configuration dialog appears, the Spellchecker configuration page tries to look up for the matching human readable name in the language name map, gets the end() iterator, and still tries to get a string from there. There's your access violation.
I'll try to conjure a simple fix for this, unless @danselmi already noticed it.