Hi,
You'll have to use the following method:
viewtopic.php?f=1&t=16826
Which ever season you are on, middle click with your mouse on each episode that you want so each episode opens in a new tab in your browser. When you find a subtitle that syncs with your video version (eg: certain release name or uploaded by a certain user), you'll find that those subtitles for other episodes will sync to your videos, too.
You'll find, shy of using a program to download subtitles, this will be the fastest way to download manually.
Or you could drag and drop your videos in a program and expect that to get the subtitles automatically. I wouldn't know anything about those programs, as I've never used them. A quick search on the forum should yield some results for that, if you're interested.
Zip files for full season packs haven't existed in several years. All subs are now categorized individually on an episode basis to make it easier to find individual episodes. Using that drive looking button in the topic above can quickly reach your 200 subs limit per day, so be careful with it.
When the .com website is fully operational and out of the beta phase, you'll be able to pick all individual episode subtitles that you want by selecting them and download those as a pack. Hopefully.
Downloading as a pack now on .org will download way too many subtitles that you wouldn't actually need. So it's not fit for purpose.
Read more about TV series split episodes and when it happened here:
viewtopic.php?f=8&t=1104
Hope that helps.