So I managed to get complete them and am mostly happy.
The basic mud was produced using my standard set of three artist acrylics, though they are much the same as the old GW paints 'Scorched Brown', 'Beastial Brown' and 'Snakebite leather'
By painting the metal work up in my usual method, GW's 3 metals then Nuln Oil wash and some agrax earthshade in the recesses.
Then trying out the new paints.
To be honest the Typhus corrosion wasn't as gritty as I expected so I'm not sure it's that noticeable.
Dry brushing the Ryza rust didn't quite give the effect I was expecting either and I expect I could have got just as good an effect from any orange.
I'll need to have a bit more of a play, maybe mix up the Typhus corrosion a bit more incae the texture has sunk, and try out Tail of Painters advice regarding stippling for the Ryzer Rust.
Still they will do for bases and look good from a distance, at least they are painted and I've managed a post. will have to try and finish some of the part compleat posts I have kicking around and schedule them up to buy me some time to do more.
Ta ta for now.