Strange behaviour multiple issues

Hi There, I have something rather odd happening running responsive AT.
Have tried several times with older and latest versions of WP and AT. Hosting is running native PHP5.4.
To start with everything seems to be going fine but then randomly when I am customising AT to suite my preference many things stop working correctly. I have no plugins installed and have tried this on several machines running different operating systems and browsers. The only way to fix this is to blow away wordpress and start again until the issue happens again.
The issue is that randomly several functions stop working. Below are some of the issues.

1.When trying to contact seller from bidding options box it just goes to the home page. Same happens when trying to contact author from author widget.
2. When clicking on an item and then trying to edit it from the edit this listing button it returns with a 404 page not found error.
3. Trying to click on members area result in 404 error also. I have tried to refresh permalinks for both these cases.
4.When in my account trying to create a listing seems to only refresh the page.
5. In page setup Home Page when trying to edit some of the objects it actually opens up one of the other objects.
6. Again in page setup – home page, when trying to add a link in Text/HTML object it will not allow me to change anything in the insert/edit link box.
Theres more but hopefully these issues might point to a common problem.
Hope its nothing simple I have overlooked.
Incase you want to see the site is https://abcsales.com.au
Thank You
Best Regards
Raff