Never happen to me to lose some piece of code because ide editor. I don't find it such a "serious error" because i don't use other editors to edit files from Upp projects, because not all editors preserve file encoding and because i don't know any situation when i have to edit project file outside of the ide simultaneous with that file opened in the ide editor.
Many ides and text editor offer this feature.
Ultimate++ has a good code browser but debugging is less perfect.
Ultimate++ is faster..
So I tend to jump between Microsoft Studio and Ultimate++..
OK, it's implemented and work great. If you have modified file outside of the ide and in the ide is not modified then the editor reload the file with new modifications. If you modified it in the ide and also outside of theide then the ide will ask you to keep changes made in ide or to reload the file. One thing you have to know is that theide save modified files at every compilation.