When trying to open a document from pcmanfm, Libreoffice refuses to open properly staying hang up on the splash. Libreoffice run fine from the console or the application menu and then I can open the document without issues. I am using Awesome WM and LibreOffice 18.104.22.168 00m0(Build:2).
Can you try the latest version of the port? I just committed a fix for bug 205922 in ports r408494 that may also fix this.