I've updated to 6.03 firmware, as it was newest available.
How have you performed an update with a not-working connection? With the emergency update?
What have you set and how have you tried to connect?

The latests control is 6.0.2.1
It is

I thought it should work, but it seems it's not.
How I can get control software to work with 6.03?
You may tell us how you tried it (LAN/USB/RS232) and check the settings. Webserver is only available via LAN and only if the LAN settings are correct.
Best is to set a fixed IP in the subnet of your router, outside the DHCP range.