In your initial post, your first voice command should have worked for you (although it could be done more simply, as PegLegTV shows).
The real question is: how were you testing your commands?
Apart from getting comfortable with how payloads and variables work, it's important to remember that when testing commands that use payloads, you can't just test using "Save and execute". You have to provide the command with the correct payload values somehow.
The only way to
truly test them is to save and exit the tree, and then issue the voice command.
The second command failed because of a number of misconceptions. You're trying to learn and do a lot of different things very quickly, so I don't want to overload you here.
But basically, you're still not understanding payloads and payload XML, so you might want to re-visit the first two tutorial videos and then take another look at your commands to try to diagnose what's happening.
Most of the things you're asking about on the forum are discussed in the first two command editing video tutorials (even if the interface has changed).
Even if you watched them previously, now that you're more familiar with VC these videos should be easier to follow and learn from.
The first video can be started around the 6m mark in order to bypass the basics:
&feature=youtu.be&t=6m05s.