Flash not testing movie properly

So, I have been working on this fla for weeks now. Just friday, I tested it and it worked beautifully nothing wrong! Then Flash crashed (CS- my computer does this to me all the time so I wasnt shocked, and my file was saved anyway) and I reopen it and test it again, and I got a small white window that had nothing in it. My fla is driven completely by code, but there are MC's and such on the stage that are always there. So I close out the swf that didnt work, and tested it again, this time it appeared but nothing functioned. I tested this on two other computers with the same result, so I gave up for the day. I come back to it today, same issue, but if I just test the same swf in Flash Player, everything is functional with absolutely no issue....

I test the same swf in debugger, and it doesn't function, and I get null errors, that in Flash Player don't occur (and didnt when flash was originally testing them- this is all using the exact same swf!)....Any thoughts? has anyone else come across this?

The other thing to note is that this occurs with older files as well, files that I know for a fact have no issue, and used to preview just fine....