BarbM,
As you noted the Sygate Firewall product was bought out and is no longer supported, which means it isn't being maintained.
Since support ended there have been multiple vulnerabilities discovered, which make the use of this firewall unsafe.
Vulnerability Report: Sygate Personal Firewall 5.x
http://secunia.com/product/254/?task=advisories
I'd recommend that you look into more current firewall products that have support, there are a couple discussed earlier in this thread.
Bitman