I will need help on this one because it seems to be that the new scintilla (which is used for the lexer) has changed a bunch... that means that the lexer needs to be rewritten which I am not able to since I am not a C/C++ programmer.
one quick solution i will try (though not the correct one) is to replace the SciLexer.dll file located on the n++ directory (which is the one causing problems) with the old version of it, that way you guys can use N++ 5.8 with my lexer until I really fix the problem which Im afraid will take longer than i expected
Tested it and it worked on 5.8, the problem is the new Scilexer.dll
Workaround: Get this
file and replace the existing one inside the N++ 5.8 folder.
If you dont want to use this file just go to notepad++ and download the 5.7 version and get the SciLexer.dll file and replace the 5.8 version with it.
Until I rewrite the lexer this is the only work around i know.
There are no noticeable drawbacks, if you find one (like another lexer not working because of the swap) please notify so i can update the post.