Right yes you can download the latest Sheetcam from Sheetcam.com (Stable version) and Mach 3 from CandCNC's website here
http://www.candcnc.com/manuals.htm "Master installer" at the bottom of the page. Use the DTHCII install file. Also PM me your email address I will see you get your again licenses ASAP
Dell OptiPlex 620 windows XP 32bit for the DTHCII. If it was a Star-Lab they can use virtually any PC with the new MarkIV THC.