It should not have any issues. The only thing I have found, when I was transfering my world from Server to SSP, the GT Oil data has got reset and changed. I am pretty sure the seed remained the same (but cannot really confirm it). But where I got Medium Oil deposite, now is Light Fuel. Oil deposit in my base (which I completely drained out) has oil again...
There is much MUCH simpler solution.
1) Get the items into your drives and have the drives in your inventory
2) Be in NEI cheat mode and SAVE the loadout (the buttons on the left side)
3) Load the new world
4) Load back the loadout.
5) ???
6) Profit
You can also stuff your base into Spatial drives... BUT... GT Machines will not retain their info so they will break and will become .name blocks.
btw you think with an evil game breaking mind. i like it. i kinda wish your pack had a few more mods to make it even more interesting. such as some more different magic mods. even though i like blood magic it doesnt seem to me to fit with gregtech the way this pack works. but maybe botania? maybe even immersive engineering as another machine mod? just for more visual machines, rustic looks. (i love multiblocks!) also with the world needing reset ive made an awesome starting spawn base for gregtech uses both mcedit and ae2 drives. it allows me to keep some basics for starting out in a new world after being so far along. well for the whole server. its just steam machines and a special shop system. but it helps nonetheless.