Unfortunately, beta1 can’t be installed with 256MB RAM because it includes 36 additional source packages, which use extra memory. See https://dev.haiku-os.org/ticket/14571.
It would be nice for package_daemon to not activate them unless enabled somewhere but there is no mechanism for that (yet?).
However, nightly images (https://download.haiku-os.org) don’t have source packages and they should work.
Please try that and report back.
We could just put them outside the packages/ directory on the DVD so they don’t activate. Too late for beta1, but something to consider for beta2. And maybe we should finally populate the Insaller option to enable/disable these extras when installing while we’re at it.
Although it would no doubt be nice to be able to install Haiku on a computer with only 256MB of RAM, I don’t believe that it would be a good use of developers’ time to stop work on something important in order to accomplish this.