Help!: My Training: How can I add 'skipping' as an activity?

My son and I are trying to get in shape and we're doing cycling and skipping.  I've been told that skipping is an excellent workout and 16 minutes is equivalent to an hour's running.

 I'd like to add Skipping so that it appears in the My Training calendar but I'm having trouble.  There's nothing really close to skipping that I can use, and anything that I try, such as running, expects information like distance travelled.  Basically trying to use any category results in it expecting information that isn't  appropriate.  There's lots of very complicated workout activities, but nothing for a nice simple regular Joe like me that rides a bike and skips rope...

I tried adding skipping as a new category, but I get the pop-up box where I enter the info, and when I  click on the save and continue, it returns me to the web page underneath, but when I try to advance to the next screen it pops up the box again and insists that I create a category.  I spent about 20 minutes going over and over this and finally gave up.  My son's lost a lot of interest as well so I think I may have to restore the situation by using a good old fashioned calendar and a felt marker.

 If someone can suggest a <tested and proven, not suggested without trying please!>  approach to being able to enter in skipping, I'd be grateful.

 The main information regarding skipping would be

# of minutes or seconds

cadence .

A rough estimate for calories burnt would likely be 4 or 5x the calories burnt from a fairly slow run.  But I'm only guessing. 

Just something someone told me - they didn't credit it to anything.  However, a quick search in google finds plenty of websites that substantiate this estimate.  http://www.webmd.com/fitness-exercise/features/skip-rope-not-your-workout is a good article on it and no doubt you can find others.

The exact  workout details may be harder to calculate but it's definitely a killer activity, especially for those just getting  (back) into fitness like me.

Until the website fixes the bug that rejects adding new activities, I can't track my skipping.  I also don't really know what category/subcategory info to populate it to, since it's not a running, gym, weight training, aerobic or other exercise.  It's skipping!

D