Pretty much... Octopus, Hot Key Net, Auto Hot Key... are the free options.
I haven't tried any of these, but believe Octopus is no longer updated.
There are a lot of HKN supporters on the boards.

Keyclone, InnerSpace and GameCommanderPro are the pay options that I know of.
I started with Keyclone, but have moved to IS for the auto FTL, PiP swap speed and mouse broadcasting.



I'm not sure if there's another issue with your keyclone or not.
I do know you'll need a copy per machine, and that is likely the issue.
Still its a one-time fee per license, which is then good forever.

InnerSpace, unlike Keyclone, is a subscription based option.
$36 per year, but good on five machines.
I'd still recommend Keyclone as the first product, but IS has a ton of nice features.