Sorry, i must have missed this one,
All you need is London - Southampton v0.9, and included in that is a requirements list. I have not used anything new so all you need is the stuff you need for v0.9.

(i.e. ukfs and magnetic platform kits (all of them)).
The signal problem is explained in the General MSTS Discussion forum.
Part 2 of the patch has been updated to fix this fault, and is currently waiting re-approval.
Cheers