[esp-r] Can't save constructions database

[Dave Howorth]

I'm just starting out with ESP-r and am having some trouble.
I've added a couple of materials to the database - straw bales and lime
render - and that seems to have worked (initially it gave me errors but
I changed the file permissions to allow me to save).

But when I try to add a wall construction using those materials the
constructions database isn't saved. It prompts me to save it and I do
try to save it. It prompts me to overwrite the file, and I say yes. Then
it gives me a dialog about reflecting changes in the database and
rebuilding zone construction, which I don't understand. But there's no
error message as there was when the permissions were wrong. Equally,
there's no change to the file :(

What am I doing wrong?

Thanks and regards,
Dave Howorth