On my 64bit windows 7 machine I encountered a problem loading delftshell.
It seems that Assembly.Load fails when loading a 32 bit assembly into
a 64 application?? Below is the exception I got:
BadImageFormatException:
Could not load file or assembly 'file;///E:\src\..etcbla\gdal_const_csharp.dll' or one of its dependencies.
From line 325 of DelftShell.Core.PluginManager.
Setting the platform target for my DelftShell.Loader project to x86
fixed the problem of loading delft shell.
Running a model in an external process did not work as well. (Same problem loading dlls).
Here's a related post.
http://www.julmar.com/blog/mark/PermaLink,guid,28d0a66c-1741-42a0-8ad0-1e2734c0e9f9.aspx