How to reduce the file size?
When exporting the file (it doesn’t matter if you are using Photoshop or InDesign) try modifying the compression to ZIP. By enabling this setting, you can reduce the file considerably. Look at the following screencap closely and try to replicate the settings I have. http://s1336.photobucket.com/user/imaleschuk/media/ScreenShot2012-06-04at104739PM_zps98e361fd.png.html
I am using the Smallest File Size (Preset) and I did a few changes to the compression panel. There, I changed the compression settings from JPG to ZIP.http://s1336.photobucket.com/user/imaleschuk/media/ScreenShot2012-06-04at104750PM_zpsccad58e7.png.html