The images shown in project GC are those on caches you own, uploaded by finders and images you have uploaded - they are listed in two groups
The top list are 'Cache images' - ones added to caches you own
The bottom group are 'Log images' - ones you have added to your finds
The images shown in the gallery on GC are just images YOU have uploaded - this figure should be the same as the count for the bottom group (or very similar at least) it is in my case
I believe this is why there may be the differences you see