the first one, is to display the memlimit alert "if it is too low, installation
may fail!" only if the Attempt to raise limit to 20M fails ($memlimit seems too
low, installation may fail!)
the second one is to change "Sysop account name:" into
"Sysop account name:" so it's stay on the same line than it's field.
Else the "name:" land front of the password field (quiet confusing, imho)