do you just plug in the crossfire tx module when using your long range (crossfire micro rx equipped) rigs and remove the module when flying your frsky equipped gear?

You can keep it in, the module only gets turned on when you select that model that uses external module.

And just make sure not to select that model without the antenna attached. I keep my crossfire antenna mounted all the time. It's flexible so it fits in my case easily and I don't have to worry about remembering the antenna.

edit: the product manual also describes potential damage to the reciever if powered without an antenna due to the capacity for two way communications between the 'tx' and 'rx'.