I have already done the workaround to change the size (sorry, it's a 'size' tween!) by setting a function to fire every 100ms. Just wondering why the 'normal' flash tween stops working when you change the colour of a movieclip.
The actionscript I used to change the colour of the movieclip is as follows:
Code:
new Color(_root.topbg).setRGB(colourValue);
Thanks