I just came across THIS TIP from Cindy Lou - The Stamping Guru on heat embossing with classic ink on glossy paper.
To heat emboss you need to use an ink that the embossing powder will stick to - like versamark or craft/pigment ink. Classic ink dries too quickly on paper but not on glossy paper!
It's kind of the same idea as embossing on vellum when using your computer printer or classic ink - the ink stays wet long enough for you to add embossing powder and then heat!
It's so cool - I've never thought of doing this on glossy paper before but I can see how it would work.
Now this means that you can emboss with the new Stampin' Up! In Colours classic ink (since there is no craft ink in these colours).