The iControl libraries should be forward and backward compatible with the following exceptions
1. When using a newer library, you might get "method not found" exceptions at runtime if you are trying to call a method that wasn't present on a previous version of BIG-IP.
2. When using a older library, you may get the error you are seeing if you are accessing a method where an enumeration has been appended to in the newer version of the product.
Both of these situations occur very rarely but are good to know about. The best bet is to update to the latest version of the library each time a new SDK is released.
Let me know if it works in your test lab so I'll know to post something about this in the documentation.
-Joe