Hi there!
Mmm... That's quite strange. So, yes when you write the code $gameVariables.value(1) you print the current value set to Value having as ID 1. So, all variables have as default value 0, but assigning a value this should change - as you probably already know -. I've done a test on my end trying to set the value of Variable ID 1 by console to 24 and it seems to work properly:
The same thing should be if you set the value through event commands. Not sure why it do not update on your end. Have you tried to use the plugin in a void project?
About your second question, you can show the money value just using this script call: $gameParty.gold() assigning it to the proper plugin parameter.
Furthermore you can change the Parameter Name from "Age" to what you prefer and you should have a similar result
Thank you for your support <3