Several programs that I attempt to run with WINE will run in the background, but not be visible in the system tray.  ALT-TAB does not make them appear.  They appear in the system monitor as processes (and indeed run normally-- zMUD is connected to the server, and Steam can still download files), and Steam, which has a tray icon, appears in the tray, though I cannot open 'library', 'store' or any other options which use the main window.  ('Settings' can still be opened.)

With zMUD: The program loads normally until I attempt to connect to a specific server.  The window then opens as it should for a split second, and then disappears.  The process still runs in the background as it should (the server disconnects after a period of time with inactivity-- zMUD asks if I should reconnect when this occurs.), though I cannot interact with the program.

with Steam: Everything seemed to run normally, and I even started a download of a game in my library.  I changed desktop workspaces, and Steam suddenly became invisible.  It still has a tray icon, and it continued to download the file (the only plausible use of my bandwidth in the system monitor), though I could not interact with the main menu.  As mentioned previously, if I attempted to open 'settings' from the tray icon, I could access the Steam settings, but nothing in the main window.

There is no crash output from these programs when run from the terminal, as they do not crash, but are simply invisible.