yeah i think your possibly right, that the lib32bz2 was an older way of doing it,
see http://askubuntu.com/questions/637113/unable-to-locate-package-lib32bz2-1-0
the problem we have is simple, we need others to update the build.sh script and issue pull requests, (no one person can have install all flavours on linux) , but then they need to be very careful they don't break things for other distros.
fortunately we will see if someone breaks the ubuntu 64 bit install , since travis build this (but its still a pain if we have to fix it) , this is why it can be 'supported'
i don't think there is anyone here, that has the time/patience to keep reinstalling new distros to test it... this is the difference between a commercial setup (which will only support limited distros as well) which has people who's job it is (QAs) , and an open source project where no one is paid to do this.
no one will thank us for support 10 different distros, which are broken on every release, and they will also be very critical if we release a version, and then it doesn't work ... its a no win situation.
here is my recommendation ... everyone use Ubuntu 64 bit 14.04, its what is tested
(hmm perhaps the build.sh, should warn this when run)
on the positive side, @johannes has checked in a pull request that someone made for arch-linux, this also makes it easier to support different flavours architectures, so if anyone wants to contribute changes thats most welcome.
sorry for the rant... anyway, upshot is if you have a better fix for the build.sh, please consider issuing a pull request.