Then you should try the latest public beta of FlashFXP 3.4 (beta 6 at the moment). This version caches directories. But... no, you can't browse directories you've never listed before once you're disconnected. I seriously doubt any ftp client can do that. It works pretty well for directories you've already browsed though.
PS: Now you can be really sorry for the bad language
Btw, while you're at it, mail
support@inicom.net and ask them to link your board account to your customer portal account. You appear like an unregistered user right now.