I'm evaluating PhpED 5.6 (thinking about purchase it) and I have exactly the same problem debug sessions ends after 60 seconds.
I switch off built in Vista firewall but it doesn't things go better.
I have router but I didn't try yet to bypass router to check if it's guilty.
I'm using SSH (cygwin and 'ssh -R 7869:localhost:7869 user@myhost.net' command to communicate debugger with Apache server)
I had no permision to place debugger extension to specified in php.ini extension_dir=/usr/local/php4/lib/php/extensions/no-debug-non-zts-20020429/ (as it was sugested by dbg_wizard.php) but I add a line zend_extension=/home/sys/php4/dbg-php-4.4.so and put it there.
Debuger seems to work but only short time - I can debug 60 s. - it is not enough to resolve problems with scripts .

Administrator of host where Apache are working said that: "As I see, that debugger is opening a port and running as a background process. Keep in mind that we do not allow background processes to be ran on the server."
Can it be a reason of finishing of session after 60 s.? If so - how can I switch debbuger to work not as background process?

Who can help me?

No, debugger does never use any background processes. Probably administrator meant your ssh tunnel.
Regarding unexpectedly terminated sessions, it's possible that your web server has configured with special timeout for the script execution and kills its own children processes if they take more time. At least, it's not php's timeout which is under debugger control.

Dmitri,

Do debugging sessions are so resources consuming as administrator of my Apache host said:

"This is a shared hosting server,..." and than he said "Well, I have been revising the situation with our administrators. Increasing the values of the Apache configuration will apply for all hosting accounts on that server, this will, as you may know increase the load of the server and thus, reduce its performance."

??
Miroslaw