How can I set up dynamic imports when hosting IronPython?
You need to subclass the PlatformAdaptationLayer class and implement the "file system" calls.  IronPython will then go to the PAL to do I/O for the files.  This also involves implementing a ScriptHost which returns the type for the PAL.  A good example of this is the Silverlight host which redirects file I/O to a XAP file.  
If you browse the IronPython source on IronPython.CodePlex.com you'll find the Silverlight host in IronPython_Main\Hosts\Silverlight\Microsoft.Scripting.Silverlight.
I'm writing a C# client application which is intended to have strong support for customisation via scripting, and I have chosen IronPython as my target scripting language. I would like to keep the user's code in the application's database with the rest of its state, but I need the user to be able to split their scripts into files and modules.
How can I configure the IronPython engine so that it will use strings (with corresponding virtual paths) as the source for imports, rather than specifying a directory in the user's filesystem? Is this possible?