You may use threads with E\+FL, but only in specific ways. If you plan on using threads it is very important you see the following example guides. See the following

\mbox{\hyperlink{efl_thread_1}{E\+FL Threading example 1}}

\mbox{\hyperlink{efl_thread_2}{E\+FL Threading example 2}}

\mbox{\hyperlink{efl_thread_3}{E\+FL Threading example 3}}

\mbox{\hyperlink{efl_thread_4}{E\+FL Threading example 4}}

\mbox{\hyperlink{efl_thread_5}{E\+FL Threading example 5}}

\mbox{\hyperlink{efl_thread_6}{E\+FL Threading example 6}} 