Though you may be able to get by with the public domain version, if you're going to be investing time in learning and using Euphoria, you'll want the full version (US$32).Euphoria comes in two different editions: a Public Domain Edition and a Complete Edition. Both editions will run any Euphoria program of any size at full speed, and will report all "compile-time" errors such as syntax errors, undeclared variables etc. The only restriction in the Public Domain Edition is that full diagnostic information for run-time errors is not provided for large programs.
The newest version of Euphoria, 2.0, can be downloaded from the "Official Euphoria Programming Page." This web site also includes more information about Euphoria, pointers to more free Euphoria code, and an on-line registration page to get the full version. Euphoria 2.0 comes in two versions, Win32 and DOS32. The RO software doesn't make use of the Win32 capabilities, so the DOS32 version is all you need.
An older version, 1.5, is available here. We had some problems running the software under version 2.0, but it worked fine under 1.5.