Note: First make sure that the pics you want to put side by side have the same height.

1. I used the add image icon, the camera one.
2. Then I delete <p style="text-align:left;"> at the beginning of the code and </p> at the end of it.
3. Do number 1 and number 2 for the next picture and so on...

Here's for my textbox:

<center><img src="http://api.ning.com/files/pOtsoGswNrA4Pfd7lpY9CQiom87jmUAo-CcvpxAJR7y4Qji672kFVeZuB*3DWnusaqptYjFlCyw-l3pqBBgob6NePEa4MupW/10.jpg" alt=""/><img src="http://api.ning.com/files/xisEFWEAEfF9y1x9zgPUGH6q13*K9sS4R64ugLOaWSHZz373l6Heb11-ufxKuVgcuIL8A2jl-o2vsBx25HU1mL0R6*gcAn75/11.jpg" alt=""/><img src="http://api.ning.com/files/zWm1m0oBnVWnSLaM*mXLCWXhtH*HQPvElP7frpF0pYz7L0xAgSt0Mt9SGZejwu16nH-TTPsowPnvq8iNnO74WiSz3zyWKXVZ/25.jpg" alt=""/></center>

I just add <center> , </center> on both ends to center it.