CIFS is supported in WCM. The CIFS implementation in WCM does not support automatic triggering of rules in 2.0.1E (it will be an option in the upcoming 2.1.0 release) specifically because WCM is multi-asset aware, and rules triggering actions on single file events often do not have the intended outcome.
An example of this would be a form for collecting content from an end-user in a front-end web app. If a user is posting say a profile, that profile consists of come personal information collected via the form along with some optional material (say, photos) they may choose to upload.
Now, the proper way to handle this transaction is to have the XML generated via the form along with any and all uploaded and associated material treated as a collection of items that together need to be routed for review and publishing. The notion of a drop-box is centered around the drag-and-drop of a single document (like a Word document) and automating processing of that single file (transform to PDF, content review). In the WCM case, you actually have more than one create event, and because of the stateless nature of a web client, you don't necessarily know in advance how many create events you will have before knowing when to trigger an appropriate rule. Did the user upload any photo, and, if so, one, two, or three? It's indeterminate.
To handle this, your web app should simply write back any and all content into a particular sandbox, and, once done with writing out all its data, execute a submit, which in turn will execute workflow.
This issue has also been raised via our internal support channel, and a more exhaustive explanation of various things related to this implementation (use of output path patterns, ways to specify to whom things were routed) was provided in that forum.
Kevin
