custom or dynamic caching
I've noticed (just visually) that the player is using a rather limited cache of downloaded data, therefore on low speed connection or a less functional clip (i've noticed that some vplay clips have better performances than other even if they are part of the same series), there are temp. interruption until the player downloads another chunk of data.
I'd propose a functionality that either downloads continuously data in background or allows the user to set a proper download cache size in relation to his / her internet connection performances.
Again it's just my observation, i didn't check the source code behind and i didn't test it on other computers.