There is no such thing as Source 2009 any more, the 4 games that used it got split into distinct engine branches (TF2, HL2:DM, CS:S, and DoD:S), and then a SDK was forked off of as well to become SDK 2013 (which is what Synergy uses as of a recent update). All those branches have continued development separately and SteamTools only follows TF2, thus Synergy is indeed not supported. That said, based on the thread you linked and the fact it loads with 1.6.2, your error is almost certainly down to a SourceMod issue and nothing to do with SteamTools. I also suggest not calling people idiots when you're incorrect (or ever, really).
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