Could not load file or assembly when trying to remove/delete Resource/Application

I have a Biztalk application that is basically a housing for a schema that other applications are using. I now want to remove this application, but am unable to from the BizTalk Server Admin Console, when I right-click --> Remove I get an error that says

Could not load file or assembly <assembly_name>.dll or one of its dependencies. The system cannot find the path specified (mscorlib)

followed by:

The system cannot find the path specified (Exception from HRESULT: 0x80070003)

So I go to remove the assembly from the Application and get the exact same error. I remove all references to it in other biztalk resources and still the same error when trying to delete the application or resource. I did notice that in the Modify Resouces dialog of referencing assemblies, this rogue assembly is listed as a dependency status of Not Found.

The strange thing is, when Messages come through, the resources which depend on the rogue assembly, still work fine and no errors are thrown (despite them using components of the assembly which shows as Not Found).

I have made sure to check the GAC and the assembly is loaded to it.

So now I have to ask:

1. where is Biztalk actually looking for this assembly?
2. is there a way I can just force a deletion of this application?
3. why does it care if the assembly is not found, when I'm trying to delete it?
4. why does it show as Not Found, yet still work?

Thanks.

I think the key is "or one of its dependencies." If it's a dependency it may be using the standard windows mechanism for finding a dll. It searches the current directory and the windows directory for them.

"where is Biztalk actually looking for this assembly?"

Look in the 'resources' section of your application in the biztalk management console. It shows a column with the location of the assembly.