I know there is support for Xterm, ZOC etc in OSX, but I cannot find the correct DirectIO for Mac to use the software FlashRom
I moved your topic to the right forum. It should get better attention here.
Ah yes, DirectIO has been renamed to DirectHW. http://http://www.coreboot.org/DirectHW has more info about it.
You're right that the link to the download is broken right now. That's due to a nameserver mixup after a domain move. We're trying to fix this, but it might take some time.
In the meantime, you can try to compile DirectHW from source: http://review.coreboot.org/gitweb?p=directhw.git (http://review.coreboot.org/gitweb?p=directhw.git) has the latest source tree which is accessible.