1) Do you have any error messages in the <X-Cart>/var/log/ folder? If so, please send them to me.
2) In order to reset the cache rebuilding process please follow the instruction here:
http://kb.x-cart.com/display/XDD/What+to+do+if+you+cannot+access+your+store+and+it+ says+we+are+deploying+new+changes
Tony.