In reply to:
Has anybody broken that optical cable input door on their equipment?
Input door?
In reply to:
Any suggestions on how to make an optical cable feel tighter in the jack?
What kind of optical cable are you using? I found when i switched out my 'stock' optical cable (you know the truly cheap one that comes with the cd player/dvdp) with something that was a quality made cable ($4.99 Acoustic Research from ebay), the plug had a much more snug fit.
Regardless, if your dvd/cd player is working without skipping or similar oddities, you should be fine with what you have.
As for the optical jack cover, i would cover any open ones with a small piece of easy to remove tape just to keep out the dust. Most units now come with inserts for this purpose.