Its no biggie IC.
I just checked it out. I also exported from GP3 into midi format and imported it into PTab. Worked great.
You should do yourself the favor of checking out ptab. I find it much easier to use (for tabbing) than GP3..and its free.
...you can't beat GP3 for its huge library...but those of us who have been tabbing a fair bit prefer it.
Now...regarding your tab...Not bad. The bulk of the work is done..and the notes are all correct (at first sight). How accurate do you want this to get? The rhythm/note selection is off quite a bit....for example the main riff sounds a bit wrong...the ringing part after the main riff are triplets...etc.
If you want to convey the right chords/notes and the basic idea, this tab works great (and is better than most out there)...if you want the playback to sound exactly like the original, there are some modifications that need to be made.