I just tested myself and I had no trouble downloading, installing and plopping in game. So I don't think Seabody's sims3pack had anything wrong.
Check your patch level:
Start the Launcher. At the bottom of the left column, you should find a text saying 'version: ....'. This the patch level of the latest Sims 3 programs you installed (game and EP's, SP's): base game is 1., WA is 2. and so on. Then, just below the this version number, you should see small icons: those are the icons of the different EP's and SP's released so far. The 1st one from the left is the Base game, everybody has this one If you hover your mouse over it, you'll get a number: this is your patch level for that '.exe'. The next icon is WA, then HELS, AMB, Fast Lane, LN, Outdoor Living, Generations and Town Life. The games you don't have will be sort of grayed out.
The Swap Shop here is not the Sims 3 Store or Exchange, items downloaded don't go straight to the right folder into your Sims 3 user folder. Track it down (C:\Users\[username]\Downloads) and drag and drop it in the Downloads folder from your The Sims 3 user folder. Start the Launcher and it should be there, under the download tab. Tick the box for this lot and install. When it's over, check it's there in the installed items tab.
Does it help?