No, because Live Channels does not have categories either.
If the reason you are trying out CosmiDVR is for the integration of channels with your native app then will have to select only the categories you really watch and be without them.
If you are trying out CosmiDVR for the features such as pause/rwd/ffwd and don't care about integration of channels with the native app then try my other app CosmiTV: https://play.google.com/store/apps/details?id=com.cosmiquest.tv
It's a stand alone app based on Live Channels and CosmiDVR and you can see your provider's categories there.
Yes it does, but because the Live Channels app is not included on Google TV you have to install it separate.
If you are not using the Live Channels app now but you are looking for the same functionality of CosmiDVR in a single app then I would suggest you to also try my other app CosmiTV which is a stand alone app: https://play.google.com/store/apps/details?id=com.cosmiquest.tv&hl=en_US&gl=US
"Live Channels" is the TVApp of Android TV OS, which FireOS is based on but FireOS. Here is the "Live Channels" app link on the the Play Store: https://play.google.com/store/apps/details?id=com.google.android.tv