Thank you all for the suggestions; I will be sure to try them out. I've already checked my SSID and WEP Key for accuaracy. Also, I do not have my router configured to filter connections based on MAC Address. And yes, I have it configured so my router's DHCP range starts at 192.168.1.120.
I could switch off the encryption temporarily for testing, but like I said before, SSID and WEP key are verified, so that's not it. I will check for the firmware, and perhaps see about upgrading AmiTCP.
There is a file named HermesII in Devs:Firmware, yes.
I will try following the AmiTCP guide next, along with new copies of prism2.device.