Other dialogs here.
The source files of some Hotlinked Modules are missing
Sources of the following Drawings are unavailable!
If this item is part of a clone, its clone will also be deleted
Polygon boundary intersects itself!
"The source files of some Hotlinked Modules are missing. Elements of these Modules are visible in this project, but you cannot update them." This happens when you take the project off network, or the modules' volume is otherwise unavailable.
This isn't a great concern because 1) the content is still visible, and 2) the warning will go away when you get the project back on the network.
The warning is more annoying in AC10, however, because it comes up every time you save or publish.
In the templates, there are a few hotlinked modules, which are assembly types. These files reside on the onion at 3 Resources/AC/External References/Modules/Assembly Types. I keep these files hotlinked for consistency. Once you start a project, you can break the links if you prefer.
"Sources of the following Drawings are unavailable!" Similar to the module warning, this means that the path to some external drawings cannot be found. This warning will come up if you are off network or a volume isn't mounted.
Also similar to the module warning, it's a temporary problem, which will go away when the project is reunited with the network. Or you mount the volume.
In the templates there are several external drawings, which represent the symbol keys, abbreviations, and general notes.
[When deleting a view] "Deleting views is not undoable... If this item is part of a clone, its clone will also be deleted." Just what it says. Clones, remember, are view folders which are live copies of part of the project map. You don't get to decide what's in them. AC's rather awkward approach to this is to delete the whole clone folder when deleting a cloned view. So, don't delete cloned views.
It would be nice if this warning were bold, rather than small and unimportant looking.
If I ran the zoo, I would simply disable the delete button for cloned views, but I don't run it do I.
[When drawing a polygon] "Polygon boundary intersects itself!" This is an attempt to improve the 'invalid polygon' warning in AC9 and earlier. Like it says, it happens when a polygon crosses itself, creating a twisted thing that won't resolve properly in 3D. You'll see this most often when doing a complex magic wand move.
The new feature is to offer a choice of how to handle the twisted polygon. I appreciate the effort to work with us, but the choices aren't helpful. If you 'regularize', you're throwing one side of the twist away. If you 'keep polygon', you get the same old bad element.
In real life, you need to 'keep' it, then observe the issue and fix it manually.