So I managed to use sci_set_marker_at_line, but when I try to use some markers, I can either get the markers for code folding, a green plus, a yellow arrow and all other options are white circle.
I have read http://www.scintilla.org/ScintillaDoc.html#Markers and tried to use
SCI_MARKERDEFINE(int markerNumber, int markerSymbols)
but it says tak SCI_MARKERDEFINE cannot be called (because it turns out to be 2040). Could you help me a little and tell me, how to set those markers properly?
If I manage to do this, then I only need to understand how Addons provide jumping to code and I guess the plugin will be ready to go. Anyway it provides now information about lines with error quite fine.