@ Yaser, I was all set to go to Mithi, until they changed the date to a week later, I have to be in ISB on 18th.
The ABS should be switched off for better braking in Gravel, Sand and snow, otherwise you just roll on top of the loose stuff rather then the tyres digging in and collecting gravel / sand / snow causing a sort of wedge in front of the wheels to slow down quickly. Also during fast travel on uneven surfaces the abs will gets confused and stopping distance is invariably increased. Disconnect the wire as Qasim said, or sometime there is a separate fuse for it. Also disengage the airbags if any, you don't want them deploying in your face on a sudden hard jump landing.
Finally my TLC coped ok with cholistan 2010. But than I was only driving it at 70% or so, Only in qualifying we tried maybe 90% or so. Firstly it was my first rally, 2ndly it was our travelling vehicle from ISB to Cholistan n back, and it was absolutely stock. We only put on a roll cage, because it was made mandatory in cholistan 2010, before that only open top vehicles had to have it, hardtop's rollcage were optional. Only weight reduction we attempted was removal of 2nd spare tyre (it come with two spare tyres). we didn't even remove the rear seats! Used our AC 20% of the time, hit an indicated 148kmph max on a straight stretch. I lifted off the accelerator on most of the bumps n jumps to try n save for remaining rally and the return jouney. The shocks were ok after 228km rally. The rear ones were possibly a bit soft, more noticible with 5-6+ people on board or maybe it was all in the mind. So changed the rear shocks eventually. The front has torsion bars, and wheel travel is relatively limited so shock survived ok!
However I would suggest to get double shocks all round. Get proper mounts (adday) made, you can later on use them for better auxillary shock. I think properly made Adday / mounts will be no more than 15000Rs and just get 4 KYB or tokico shocks which will again be approx 15000rs. Good Luck!