Finally I have managed to get rid off all the errors I had upon install Chevereto. Chevereto is now working perfectly fine, but it tends to block other directins. I have another system installed at my host in a new direction, and when I try to access it at its admin page chvereto blocks the page and says "Not Found". I know it is because off chvereto cause it is using cheveretos's theme at the page where it says "Not Found". How can I be able to access directiories without beeing blocked by Chvereto?