it's interesting that this crops up every so often.
MC is actually a really competant file manager, as well as a collator.
I cannot remember when I last used explorer to work with media files that MC has a handle on.
Try to think of MC as an explorer replacement for your media files. Explore (no pun intended) the possibilities open to you via MC's internal "drives and devices" and "My computer" areas. Right click on an audio file, and look at the selection of library tools that you have at your disposal. Their names are pretty self-explanatory. Try to envisage what you could do with those. Remember, when you perform file operations using MC's tools, MC will maintain all the database links and information for those files.
If that doesn't appeal to you, either because you don't trust it, or perhaps it simply doesn't fit with your workflow requirements, then I think you may be better working out an alternative solution, the 'mediacenter file' type has been around for as long as I remember, despite numerous requests similar to yours over the years.
I can't comment regarding the sleeptimer plugin as I've never used it.
-marko.
