Kitteh, "I bought it when they had a $99 special"

As long as you have your login details nothing is lost. I assume there will be an upgrade price tomorrow at least you can download a new trial version!

It is not obvious how to use MD for 3D cloth though.
Do not fall into the trap of making those elaborate "real world patterns" which the MD Team loves. Use simple patterns. Right and left front + back + arms will often suffice. Instead create you fabulous designs using internal lines. ("select all" shows their positions) These lines will carry over to your 3D modeler which you then can use for material zones and/or UV areas. Be sure that your the checkerboard pattern is distributed evenly. (Hedaus UVLayout will do that automatically)