Running 1813 without code completion. Same problem. With a file open in the editor and more than one plugin loaded, closing the project causes the "waiting" cursor I described earlier. BUT, closing Code::Blocks with the file open exits cleanly. This is different and may be what sgsong reported about 1804.
While I have code completion attention... I do note that I have an array of structures, and accessing as struct. something, After the dot code completion comes up with all the global symbols. Nothing related to the struct members.
And now for some reason, I can't build my old project. "undefined main" when just compiling one file. Oh well, that's yet another issue.