Can it be that this machine is running low on memory?
What happens, if you ran a "hello world" CGI script via NaviServer? (see example below, put "hello-world.cgi" into your global www directory).
Do you have the chance to compile the newest version of NaviServer from bitbucket [1]. I've just added more debugging aids, one can now turn on at runtime debugging of nscgi via "ns_logctl severity Debug(cgi) on".
-g
config snippet
#
# CGI
#
ns_section "ns/server/${server}/module/nscgi"
ns_param map "GET /*.cgi"
ns_param interps cgi
ns_section "ns/interps/cgi"
ns_param .cgi "/usr/local/ns/bin/tclsh"
hello-world.cgi
puts "HTTP/1.0 200 OK
Date: Monday, 06-Nov-95 17:50:15 GMT
Content-Type: text/html
<html>
<body>
Hello World
</body>
"
[1]
https://bitbucket.org/naviserver/naviserver/overview