What processor or gateway can POS eXchange work with? Processors such as TSYS, Global, etc., or gateways such as Authorize.net, PC Charge, Merchant Link, etc.?
The software is not available anymore. There is no information about it or about its developer. Most of these applications should have a README file included in the installation directory. Open the README file and there should be a list of compatible devices. Alternatively, access Help > About. Probably, you find some contact options there. Since no website is provided, that's the only way to acquire the contact information.