Looks pretty good. I didn't have a chance to look through it fully but for the Rapidshare api checkfiles_v1 the return value of 1, which you have, means it can be downloaded but the values of 2, 3 and 6 can also be downloaded.

So on line 226
PHP Code: 
if ($fStatus==1) 
would need to be something like
PHP Code: 
if($fStatus==1 || $fStatus==2 || $fStatus==3 || $fStatus==6) 
or else you'll be binning Rapidshare links which aren't dead

Extract from Rapidshare API Guidelines
Code: 
		5:Status integer, which can have the following numeric values:
			0=File not found
			1=File OK (Anonymous downloading)
			2=File OK (TrafficShare direct download without any logging)
			3=Server down
			4=File marked as illegal
			5=Anonymous file locked, because it has more than 10 downloads already
			6=File OK (TrafficShare direct download with enabled logging. Read our privacy policy to see what is logged.)
I'd advise you to use 3 aswell incase their doing maintenance etc.

I'll have a better look at it later.