I went straight into SGX, which is a real challenge, but its brilliant and I've finished it
I've only had a few of the bugs that people are talking about here, but I've had quite a few that maybe (I read through the last few pages pretty quickly so not sure) haven't been mentioned.
1. If you interact with the thing covering the stairs leading to mahogany hideout the game freezes (luckily i saved beforehand)
2. After you beat TR in mahogany, and you go through that gateway place where TR usually charge $1000, apparently there must be some invisible rockets still there, because I got charged $1000 even though the only person there was the normal gateway person. Also when the TR guy heals our pokemon at this place, his sprite changes.
3. . You can't use FLY or TELEPORT in the sea or inside the whirl islands.
4. I think that the only way you can escape tin tower after catching HO-OH (I CAUGHT HO-OH WOO HOO!!! took ages tho lol) is via an escape rope.
5.Are there meant to be wild pokemon just outside ice cave? (in the tiles near carlos that are coloured like ice)
I'm not sure about normal SG but this all occurred in SGX.
PS WOOHOO i caught squirtle (not saying where) but false swipe is a must.