Yeah, I have noticed something similar as well, though it had nothing do with using items or skills that were not ready (I have double-checked the code, and if a skill isn't ready, the packet is simply discarded without changing the state.
I managed to reproduce a freeze though, by interrupting casts (simply starting to walk mid-cast), then stopping, and immediately starting to walk again. With that, I was able to look more closely with what is going on, and found a race-condition in the client prediction code, which I added a fix for, on today's update. We'll see whether it works better now.
If you get webbed, that's someone else's spider. Web-Shot does check affiliation before triggering.
