Modelling isn't really DayZ specific so you could follow any tutorial series and it would be applicable. Though it's up to you which program you use, I'm guessing most people use blender because it's free so I would start there. I would also recommend checking out ofp2's post here, it looks incredibly promising
As for point 2, unless you have a lottttttt of free time to comb through all the scripts and find useful tidbits you'll have to wait until they release documentation or examples, whenever that may be (Hopefully soon but I'm not holding my breath).
Sorry I couldn't be of more help.