Ever cracked your brains out wondering why your dynamic text field does not show the text when its masked??? I have been struggling with this problem from some time now.
All you need to do is embed characters. Select character sets that you want to embed from the embed option in the text field properties. Characters that you have embeded will be shown … none others!!
Yes, I am also one of those troubled souls when it comes to getting your project work cross-browser. It drives me crazy getting things to work in the exact same way on IE and Firefox.
Problem 1:
One of the flash intro’s I made ran very slowly on Firefox. It worked just perfect on IE. The intro was jerky and gave a feeling that something heavy was getting downloaded in the background.
Fix:
Remove “Transparent Windowless” option (if you have selected it) when exporting your flash movie and it will work like a charm on Firefox. Worked for me, should work for you too 
Problem 2:
I exported a flash movie as 100% to fit perfectly to the browser and resize as and when the browser was resized. It worked just perfect on IE. In firefox the movie got loaded as a small box. It was not even the actual movie size.
Fix:
Remove the < !DOCTYPE> tag from the page where you are showing the flash movie. The movie will now fill the browser and resize as you resize your browser.