The test results you have selected are very old and may not represent the current state of Wine.
Selected Test Results (selected in 'Test Results' table below)
Adding and editing source, headers and resource files works.
Saving projects works.
Opening projects and files works.
What does not
The templates are incomplete so you will have to make your own templates from scratch.
It does not understand wine's .rc file format so you can't use this particular resource editor, for example, to edit the look and feel of Wine's builtin program suite, such as winecfg notepad or clock.
What was not tested
Project building (see comments).
This is the Windows version running under Wine, for testing purposes only.
If you want to actually compile things cross-platform on linux, please use the Linux version which features improved Wine integration.