shudn't yur UPS vendor whom you bought it from have a compatiable software on run on your SCO platform?
Most times is just connect your box thru the UPS, and connect a serial cable from UPS to the box. Then depending on the software I think you need to install a client software to run from the box and test connectivity between UPS and SCO then further parameters in the software to instruct the server what would happen in event of power failure the shutdown sequence.