Timber frames

[Alan J.Birney]

I was wondering what the best timber tratment for timber frames is.
Previously I have used creosote,but tradditional creosote is no 
longer available for d.i.y work-due to health concerns I understand. 
In its place is creosote substitute-how good it is I do not know(I 
bought some for the exterior of the campanile last week). The "new" 
creosote seems similar to the old creosote but what it is like time 
will tell.
I will be renovating(with others) a three bell installation and the 
intention is to treat the frame with some sort of preservative, 
hence the enquiry as to the best product.
Also does anyone know what the real safe level of movement in a 
timber frame is at sill level of a frame? The only data I have seen 
about frame movement is only in relation to affecting the go of 
bells, and to be honest, I have seen frames with more movement than 
th qouted figure and the bells go well.
Finally, how easy is it to make a curved slider, or are we 
better off getting one of the bell hangers to make one-we dont have 
the broken slider-it was binned in the 1970s.
Alan