As TuneText Builder's output is a perfectly valid HTML code, it should be compatible with any eBook Compiler.
In practice, however, many compilers add their own, - proprietary! - restrictions as for presenting HTML content.

For example, several famous eBook compilers override onkeydown listener of any user's JavaScript code (usually for assigning access to eBook's shortcuts). Under these circumstances, no JavaScript program, including TuneText, is able to implement its own onkeydown function. This means that such TuneText events as pressing Ctrl-3, and even Enter, are not be processed properly.

As a result, many eBook compilers support TuneText partly.
For example, while TuneText Highlights are supported by actually every eBook compiler, the Edits are not.

If you are an eBook compiler developer, please note:

To support Tunetext, an eBook compiler must use the Internet Explorer as its rendering engine (most compilers do).

Also, eBooks' software should not use for processing its content files the (temp) directory that is randomly defined at a runtime. This prevents the Microsoft User's Behaviours, - the main underlying engine for TuneText, - to correctly define such locations when the eBook is revisited.