Thanks. Yes you're probably right. Though if you still have zipped package, please could you do me a favour and md5sum your download so at least I know I'm using same download.
md5sum flashtool-0.9.23.1-linux.tar.7z a68d331f710b78f7eaf4350e70d3e693 flashtool-0.9.23.1-linux.tar.7z md5sum flashtool-0.9.23.1-mac.dmg 26affb08e4421292ed6858c2b8688c1e flashtool-0.9.23.1-mac.dmg