alright, mission accomplished. i picked up a 256mb card and everything worked like a charm. just a polite suggestion: perhaps eventide could explicitly "strongly recommend" a 256mb card or smaller and let the machine do the formatting. the manual states "other capacities…will probably also be suitable" but this (while entirely non-binding) seems to be somewhat inaccurate. i dunno, maybe it's just that i'm the only idiot with a big card and a mac who had a hard time with this.
either way it's all sorted out now. thanks to nick and italo for their help.
-jim
