I use WPLMS theme.
I have succeeded in installing and activating the q and a plugin in my site.
But your instruction as follows doesn't work for me.
I had no problems with 1, 2 step but when I follow the 3rd step, which says "Visit http://yoursite.com/questions/ask/ to create your first question."
http://smartvoca.com/questions/ask/ just lead me to http://smartvoca.com/about/
What's wrong with 3rd steps?
1. Go to Settings -> Permalinks in the site admin dashboard to check your permalink structure. Q&A uses pretty URLs so rewrites and pretty permalinks must be enabled. Your permalinks can be anything but the default permalinks.
Checking your permalinks
2. Go to Questions -> Settings in the site admin dashboard to assign capabilities to the roles of your choosing.
Questions > Settings
3. Visit http://yoursite.com/questions/ask/ to create your first question.
Asking a question with the FAQ plugin