SixBit can import items from eBay and will keep track of any listings created from within SixBit. Items not listed with SixBit are not tracked in SixBit by default. An option is available to turn this synchronization on.
The listing count on eBay does not match the listing count in the "Running Listings" folder.
There are a few things that can cause this issue.
First, by default, SixBit will not keep track of any listings that weren't created with SixBit. If you created listings with another tool, they will not be shown. The second thing that can cause the counts to be different is variation items. When you view your listings on eBay, they count each unique variation as a different listing. We only count each listing as a listing. Therefore users who list with variations will see a higher number of listings on eBay than in SixBit.
To retrieve items from eBay that were listed with another tool, you should do a fresh import from eBay from the Ribbon Bar in Sell Items mode | Import then choose Import from eBay. If you would like SixBit to continually retrieve new listings from eBay even if they aren't created with SixBit, go to File/Application Menu (the File button or little orange guy in the top left corner of SixBit) | Options | Refreshes and check "When refreshing, automatically create new items for listings that are not in the database."