And you did that very well.

plugin Filename:NPSWF32_15_0_0_152.dll = Adobe Flash Player

Update your Firefox here;

Download Firefox Full Installer For All languages And Systems {web link}

Update your Flash Player v16.0.0.235 https://www.adobe.com/products/flashplayer/distribution3.html

You can check for problems with current Shockwave Flash plugin versions and try this:

• check for updates for your graphics drive drivers
  https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration
• disable protected mode in the Flash plugin (Flash 11.3+ on Windows Vista and later)
• disable hardware acceleration in the Flash plugin

See also:

• http://kb.mozillazine.org/Flash#Troubleshooting