See Did CC 2014.2 break textItem.size?
The code for work-around is here:
http://ps-scripts.cvs.sourceforge.net/viewvc/ps-scripts/xtools/xlib/PSCCFontSizeBugFix.jsx
You need to change your code to set the font size like this:
myTextRef.size = 45;
if (myTextRef.size.as("px") != 45) { PSCCFontSizeFix.setFontSizePixels(myLayerRef, 45);
}