Just got around to playing this and yes I know I'm a few years late 
Anyhoo - got it all running how I like it and was enjoying myself until I get to the hovercraft. As soon as you go outside the frame rate drops to <5fps and is pretty much unplayable.
There are no newer patches for it. I got the budget version which is already V1.01. There are no specific fixes on Ubisofts website and searching a few forums has shown up nothing
Anyone experienced this before and got a work around?

Anyhoo - got it all running how I like it and was enjoying myself until I get to the hovercraft. As soon as you go outside the frame rate drops to <5fps and is pretty much unplayable.
There are no newer patches for it. I got the budget version which is already V1.01. There are no specific fixes on Ubisofts website and searching a few forums has shown up nothing

Anyone experienced this before and got a work around?