CoreMelt V1 (FxFactory version) should work in snow leopard as long as you have the latest version of FxFactory installed.
However there is a broader problem which can prevent any FxPlug plugins appearing for users upgrading to Snow Leopard.
we recommend you try installing this update:
http://www.apple.com/downloads/macosx/apple/application_updates/pluginmanag...
If that does not work you may need to reinstall FCP from the original disk and then run software update to update to the latest version, then run our installer again. It appears for a small number of users the upgrade to Snow Leopard corrupts library files that are needed to make third party plugins work.
