In respect of item 1)....
my advice would be to have a look at the linkage mechanism
at the gearbox. It's the most common complaint/issue.
http://www.forfour.co.uk/forum/index.php?topic=3070.0or...
http://www.forfour.co.uk/forum/index.php?topic=796.0If that fails to cure/rectify the problem, then I'd suspect the clutch.
In respect of item 2) have the
geometry checked, not just the tracking.
My CDI felt weird after I fitted the KW's, but was transformed completely
after being checked and set up via a 4 wheel overhead laser set up.
('Wheels in Motion' of Chesham).
Usually you'll find that the only place that has this sort of expensive
equipment is one known to specialize in setting up race cars (as well as
high end road cars). It cost me £72 for an hours work, but well worth it.