Have you considered using Webmin? That is a regular Linux web-based configuration utility, which can also be used in Clarkconnect. I've found it very useful, if only because it allows you to see things visually. SSH shell access is nice, but is quite a long way from your typical windows setup.
You're not the only person on this planet having problems with routing and IPtables. Use that fact, and google.com to search for solutions. Try sites like Linuxbeginner.com (even if it sounds cheesy) - they might have the perfect manual to get you started. FYI, I have set up Debian without too much knowledge (trial and error), and have found that most, if not all programs that need it will ask you during setup if you want to have them start up automatically.
Overall, Clarkconnect isn't bad (I thought it was extremely good, in fact), but it lacked features I needed. If you can do everything you need with it, by all means, keep it.
Finally, system requirements can probably be found using google as well. Or try the homepage of the developers - they can probably help you out. The Linux community tends to be rather friendly towards "new converts"; well, some in the community anyway.
