I haven't been involved with this game for a long time now, but I shall make a small statement about version choice.

I keep backups of all versions of this game. Except 1.1.4, which slipped through my fingers before I could back it up. I could possibly make a patch program if someone teaches me. Anyway, assuming nothing else changed, the latest version 1.1.5 should be the best choice for speedrunners because it has significantly shortened the tower minigame, thus saving 30-50 seconds.

Older versions mainly focused on bugfixes and changed how or whether certain timesavers worked.