Freelander clutch/gearbox oil leak - HELP PLEASE

Hi
I have a 2004 TD4 Freelander which was a non-driver when I bought it as the clutch was shot - it wouldn't drive at all - It started ok and is quite tidy with a relatively low 96,000 miles on it
I had a Valeo clutch kit put into it and we took out the dual-mass flywheel as it was shot and fitted a standard flywheel & kit & new hydraulic thrust -the bell housing was dry, no issues to concern us
Put it all back together - ran well and done 200 miles - then it started to leak gearbox oil out of the bottom of the bell housing
Sick to say the least but hey-ho that's life - full of challenges
We have taken the gearbox out again and the gearbox oil is leaking from the tube the thrust sits on
Removed it - "o" ring and seal in there - also replacing the lower shaft blanking plug as good measure
Question is: Why has it started leaking now? the seal is not hard, the spring wire is still on it
Has fitting this standard clutch kit caused an issue I am not aware of?
I notice the spigot shaft end (that goes through the clutch disc) doesn't sit in the bearing in the end of the crankshaft on these - why is that? Its like not supported? not like what I have experienced on tractors etc
There is a fraction play on the spigot shaft but very little and it never leaked before we changed the clutch
The shaft is also ok where the seal runs too
What makes it worse is the gearbox oil has ruined the new clutch disc too
I dont want to put it all back together then end up with another leak and yet another ruined clutch disc
Any advice would be greatly appreciated
Ian

There's no spigot bearing in the end of the crankshaft on most FWD gearbox configurations. The input shaft is supported on 2 bearings in the gearbox housing, so doesn't need a crank spigot bearing.

For the box to start leaking after the clutch was fitted. Suggests to me that the box was allowed to hang on the input shaft, during the removal or fitting stage. This could well bend the input shaft, causing the leak you are getting.
So before the box goes back in. You need to check the run out of the shaft with a dial gauge. Anything more than 1 thou would indicate a bent shaft. A bent shaft will always leak, and shouldn't be used.