Admin widgets page errors

Problem: Theme sidebars are not visible, widgets and screen-options are not drag-able/click-able in admin widgets page.

My site worked like a charm with a premium theme i used for 3 months, but two days now i am having the problem i mention above.

Problem occurs only with the premium theme. When i am switching back to Twenty Thirteen sidebars and widgets page works fine.

I have to say here that everything else is working fine except this and theme options.

With my knowledge of wp and the help of theme support i did the following steps to try fix my problem.

Not Worked
de-activate/delete all plugins from db and ftp
re-upload everything except wp-contents folder
delete/re-upload theme files

As last step i created a new database from my cpanel change setting in wp-config pointing new db(same php files) and install wordpress from scratch.
Install premium theme
Activate my plugins
VOILA problem solved…

But now i had to import my posts-pages etc.
First i tried the easy way to upload my posts table through phpmyadmin.
When i did that problem come back again.

I start hole process from scratch again and this time i tried import from tools/import as xml file.
Split the xml to 5 files and when i upload file 3 of 5 problem occurred again.
I checked when file 1 and 2 of 5 uploaded and everything worked ok.

For now i restored my wp-config file back to old database and waiting for new ideas.

Have no idea what to do.

PS. Changing of theme is not an option.
Thanks

Alex