The body lift achievable easily on a Kia Sportage is about 35 mm due to the captive bolts in the chassis, although a 4" lift is available in the US it requires a bit of welding. A rear shocker relocation kit (also needing a bit of welding to the rear axle) is also available. A spring lift is available, Ironman Suspension sells a 2.5" (65 mm) lift (or will do very shortly - my vehicle is their test mule).
As for your transmission query, I havent heard of any problems in the States with the auto tranmission linkage, it will just sit a bit lower. The only problem is the tranfer shifter needing a bit of clearancing to the body.
I am about to get the 35 mm body lift, and shortly the rear shocker relocation kit (not absolutely necessary), which should allow 31x10.5 easily, and up to 33x12.5 with a bit of rubbing. You will need new rims15x7 with 0-plus 12 mm offset (Spook rims??) or 15x8's with 0- minus 12 mm offset, you need about 3.5-4" backspace.
Try these sites for more info:
OzKia
4X4Wire Kia Forum
A couple of Yahoo groups too:
Extreme4X4Sportages
KiaSportageVsTheWorld
BTW went out with a couple of guys from another list up to the snow, both had Nissan Patrols. Spent the better part of the day digging/snatching/winching one of the Patrols out (granted he was the laed vehicle). I got pulled out three times (bottoming out mainly, one was a fairly long tow) but I was on stock 205/70R15 highway rubber. They were on Cooper 31x10.5 H/T and the lead was on 33x12.5 MT/R's. I was tail end so I was following in some pretty deep and churned up tracks at times so that along with the tyres I knew I would get stuck at some point. In short the only thing that let me down was tyres.....
HTH