I wouldn't call 64Mb "small" for memory, it's tiny. Even 20 years ago 64
wasn't really enough. The introduction of kernel relinking on boot has
been noted since 6.5 (or was it 6.4?) to make tiny memory systems
obsolete. They simply can't cope. Theo has noted he has other projects
in the pipeline that will make that situation even worse. The only thing
I can recommend is to stick to an older version of the OS and not use
the machine for anything needing web browsing. It can still be a useful
console terminal to headless devices, for example.
Good luck,
Noth