Hello, first of all thanks for your help!
It's interesting that you can't reproduce this - it's perfectly reproducible for me (and I also just confirmed that with the W8.1 machine).
Step by step guide:
- Take care both of these checkboxes are unchecked. Close CB.
- Open the first project by double-clicking the .cbp project file from whatever shell (I use Total Commander).
The project and all its open files show up in CB.
(BTW, it doesn't make a difference if you open the first instance directly or indirectly.)
- Open the second project by double-clicking its .cbp project file.
The second project and all its open files come up in the same instance of CB.
It should however open a second instance of CB.
With "messing it up" I mean: when the second project is opened in the same instance, all of its open files are also opened. However, in the tab row there is no way to distinguish between the files of either project. Say, I am working on two independent projects simultaneously (since they communicate with each other, for example), and both of them have files of the same name (say, main.h, main.c, pindef.h etc. pp.). Now all these equally named, but completely different files of two projects (that reside in completely different paths as well) appear side by side in the tabs as if they'd belong to one single project. That truly is a mess.
I don't speak for multiple tab rows. I wanted to emphasize "all files of all projects". If more than one project is opened in a single CB instance, it should always show only the files belonging to the currently selected project. Never all files of all projects, several of them equally named.
Tilmann