Ruhfuss
Savant
Interesting that you used characters from GSF, somehow I forgot you could do that...
GSF is IMO the weakest of the fantasy-themed Gold Boxes, but it made my first (seriously!) run through the "real" CotAB easier, since I could keep the items from GSF. I played with a party of 3 Paladins and 3 Rangers, and started dualling around 50% through SotSB.
Did you use any additional software like the Goldbox Companion?
I'm a pure Linux user, so no. While I think GBC is a cool tool, needing to use WINE and the windows version of DosBox is not (that's more like really crazy). It's not so bad, however, because some of the stuff that GBC does can be replicated with a hex editor.
Tools used: Memory, meta-knowledge and the clue books.
There's this endgame fight in Treasures of the Savage Frontier with a lot of enemy fighters, as well as about ten or so spread out high-level clerics who all get to bombard your party with Hold Person before you even get a word in edgewise.
Pre-buff with invisibility to negate the enemies initiative advantage?
I love Pool of Radiance as much as any grognard, but GSF > COTAB > TSF > SSB > POD is probably a better story and more coherent timeline.
Though you can always do POR > GSF if you don't mind being horribly high level for GSF. That packs in as much goldbox as possible.
One can only move PCs between games with a similar enough engine version, or by importing from a direct predecessor. The longest possbile chain to my knowledge is:
PoR -> (Curse) -> GSF -> Curse -> SotSB -> (PoD) -> TSF -> PoD