Ebay short shifter fitted, delays in gear changes

Never owned a short shifter, but as they are mechanical in nature, I'm assuming not being able to instantly slot into gear is probably more likely to be gearbox or clutch fault...unfortunately.
How does it go when the cars stationary and engine turned off?
If it works fine, could it not be a clutch issue, or perhaps even as its so blinking cold at present a gearbox oil thing?(is it only from cold, or once the engine is warmed up also)
If you have the same gear selection problem when stationary maybe the short shifters out of alignment somehow or the gearbox has a problem.
..I'm brain dumping here, and no mechanic so don't take my word on anything.

Does it have an uprated clutch?

Some clutches get dragged into the flywheel at high RPM and cause the clutch to bite and make shifting harder.

Readjusting the shifter shouldn´t help anything, but its worth a try as its free.

Could also be worn out syncros, but its not normal to have alot of syncros go bad at once.

Maybe fresh gearoil could also mask it.

first thing id change would be the gearbox oil to Oem oil m8

Does it feel notchy or stiff when the engine isn't running? If so it might need the linkages adjusting.

This stuff is good, you need about 2.4 litres: http://www.ebay.co.uk/itm/161133108640

Might be a stupid question, but with changing gear quickly are you pressing the clutch in fully?

Probably the race race oil, isn't it to thick for standard road use

What rating is the gearbox oil? I used some Millers stuff that was slightly thicker than OEM recommendations and it made the gearbox far too stiff.

readjust the linkages

http://vimeo.com/6881683

Its the southbend doing it, they are notorious for doing it.

Al Mac hated his... Mine did it once in my LCR and never again.