Q A style problems

Hi there,
I've recently purchased Q&A plugin.
However, After Q&A installation there was huge mess in my style. The plugin didn't work as I expected with my Wordpress custom theme.

These are the problems that I've faced in my website After Q&A installation:

1. my default theme didn't load correctly.
2. Sidebars disappeared.
3. Q&A appears on the right side of the page.

The following link shows the problem:

Note: I've tried to follow you instructions inside readme.txt file but I it was not clear to me what to do exactly.

Please advice/suggest.