I would like to explain you about AppWithPlugin from Microsoft website. And I have implement free flying assemblies like you don't need to worry to write path of <filename>.dll in plugin directory for example:
That is a problem. I invented magical function "to read" and "to list":
Example simple like you would like to know with all loading assemblies: Replace with pluginoaths to "PluginPaths Result: That is all. I hope it can work also for adding and customizable plugins for Entity by best coder "SoloKiller" I think he can make customizable plugin.dlls like who want add func_door or prop_static function with Entity class than Sharp-Life loads a lot of plugin.dlls like FuncDoorForEntityPlugin.dll or Sledge Editor with plugins like create more advanced primitives etc..
I hope you know about magical read-and-list.
It is not hard. I wish you great day and stay your health!
I see that it is not good way if you can't open other assemblies like OtherPlugin.dll or whatever.