rockshox tora 302 sl help

Hi, i have recently got hold of a pair of 2008 rockshox tora 302 sl forks and have a couple of issues i was hoping your combined bike knowledge could solve.

1- the forks seem to be shuddery when you compress them.

2 - there is small amount of oil gathering on the oil cap on the bottom of the forks

3 - the preload adjuster has broken off (easy to replace?)

any help would be greatly appreciated, would rather not have to pay £££ for a service!

thanks, Nick