how can i check what version i have it patched to?
I am not sure what your question here is exactly. Please try and rephrase.
The only way to do this is to do a system restore to a time before you applied the sylvan patches as I believe once you apply them they over-write your version number. The other way is to compare with other people items in the game they can see that you can't and vice versa.
If at all in doubt, just re-install to patch where you want it:)
-Ironhand