(ET) Alltrax, key switch, and charge/run switch

[Steve Gaarder <gaarder ecovillage ithaca ny us>]

I just installed an Alltrax in my NiCd-powered E15.  Nice and smooth!  I 
do have a couple questions about how it is wired up:

The Alltrax instructions, which I followed, have the controller powered on 
all the time except when the charge/run switch is set to "charge."  I 
presume this is so that the anti-roll feature is active most of the time. 
My concern about this is that if the tractor is on a slope and the charge 
switch is thrown, it could start rolling at a time when the user is not 
prepared to handle it.  I think it would be better to have the key switch 
shut off all power to the Alltrax.  THen, if it were to roll, the driver 
would still be on the tractor and can do something about it.  Are there 
any drawbacks to doing it this way?

I would like to replace the charge/run switch with a relay activated when 
the charger is turned on.  THe only downside I see to this is that the 
batteries will be connected back to the Alltrax while the voltage is still 
quite high from the charging.  Is this likely to be an issue?  What is the 
max voltage the Alltrax should ever see?

thanks,

Steve Gaarder