Trouble with mapping Akai LPD8 and VCI-100 to Traktor Pro

Hey guys,

Right I recently got an LPD8 and have been setting up a custom mapping to allow me to use my VCI-100 and LPD8 to control Traktor Pro at the same time. And most of the time it work fine.
However, I have come accross a few problems.
The most annoying one is that if you are sending quite a lot of signals from either controller Traktor will sometimes stop recognising that controler. You then have to go into the setting and uncheck and then recheck that controler for it to be recognised again. I never had this problem when just using the VCI-100 on it's own though.
I am not sure if it is just because
a) my computer can't handle it
b) I have also been trying to set up the maping for the VCI-100 to be in scratch mode for one of the top two decks with the "vinyl button" on and the bottom when "vinyl button" is off.
c) something I don't know about.

Second problem is Traktor Pro doesn't seem to like the whole using scratch as descibe above on two decks. It will always not respond to one of the bottom decks. However, it copes fine if the bottom two are only set to seek or CDJ-jog.

Any help or thoughts would be massively appreciated.

Cheers,
Aran