I have no idea why that command is crashing your (Windows based?) Server. It makes no sense to me that it would crash one type of dedicated server and not the other type. If you could get some error logs i would have something to look at.
I have already tested it myself in L4D2 and it works flawlessly for the brief moment that I Gave it (I didn't have long) it would be appreciated if you don't go trying this just yet until I've had a good chance to test and debug it on my server first. When I release 1.5 I will say go ahead with using it on L4D2, until then I'm afraid I will offer no support.
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