The latest hotfix for App-V 4.6 SP1 has been released. It is available for you under the Packages node > _CM > AppV > _Client
You'll see both the App-V 4.6 SP1 client package as well as the App-V 4.6 SP1 hotfix 2 package. There is no need for hotfix 1 package, as the hotfixes for the App-V are cumulative.
To determine if you have the latest App-V client (with hotfix 2) the version number should be "18.104.22.168081".
If you have any clients with a version less than "4.6.1.00000" you will need to run the App-V 4.6 SP1 client install program first, reboot the computer, and then install hotfix 2.
NOTE: Test in your environment. Both installs suppress reboots. When you push either update the computer will be need to be rebooted before the App-V client is functional again.