Many developers have been asking for ColdFusion Builder support for Linux for a long time, and there have been a number of requests to the Adobe forums, bug trackers and support groups for this exact feature since it's initial release.
One ticket on the bugbase reappeared in my inbox yesterday dealing with this very request, but sadly not for any good reason.
Initially reported in 2011, "ColdFusion Builder 2 Won't Run Under Linux" (bug #2832512) has been commented on by a fair number of people (24 is a fair number in my book), but sadly the ticket has been closed and the reason marked as "not enough time". Say what?
Come on, Adobe. Two+ years seems like more than enough time to me to add support to a plugin product that is based on Eclipse which runs beautifully on Linux. I'd love to know the actual reasons behind the closure of this ticket, as I don't buy the lack of time as a reasonable offering.
So, bottom line, if you're looking to use CF Builder on Linux it looks like you're out of luck. Sorry.