Actually, VideoWave has never had any 'burn' capability... MyDVD is the application where burning is done. Sad to say, you will find this version of it lacking
VIdeoWave does have the ability to Export As and in there you can choose the output you wish to use after edit. That is best to use if movie authoring (burning) is not your final solution. Use it for things like edit & effects for a single clip that is going to be part of a larger multiple clip project. Likewise if you want to make a clip to stream with or use in a phone or pad device, that is what you want to use
There is another button in VideoWave, 'Send to MyDVD'. In the NXT 5 & 6 versions it will create an intermediate file in the proper format for MyDVD. You still have to open MyDVD and load that file into it but think of it as Export As only with a pre-set that will put it in the proper format for MyDVD.
You will likely have more questions, so feel free to ask.