I wonder why there are so few enquiries about the Tango.I'll start it off.
Tango is a walking dance. There is no swing. There is no rise and fall. There is no sway. We do not glide into our steps. Most of the steps for the man are heel leads with a few inside edges of the ball of the foot. The knees veer in towards each other which results in the dance curving anti clock, and thus the inside edges of the foot being used when it is applicable.Look in the technique book fo these. In my opinion the lady has the hardest job in this dance. One more thing. Don't smile, keep a straight face. That should get the ball rolling. For the correct stance for this dance you must find a good teacher. Right from the very start the feet are not parallel. The RF is level with the instep of the LF. Lady the opposite. Keep returning to this position after for instance a Closed Promenade. If you have a tape look at the feet. All of the above is the International Style of Ballroom Dancing.

what about cbm and cbmp?

CBMP on the first walk none on the second. CBMP on the Link. Better to be explained by a good teacher. The stance or initial setup has everything to do with the steps.

One of the hardest things to do is correctly connecting the lady's left arm-shoulder and the mans right arm-shoulder. This is a base for the snaps and good tango movement--it locks you in. Especially hard for the lady since she hooks under the arm. It also helps if the height difference is not too much. The guy needs to be careful and not kick up his right shoulder when compensating for the tension created.

Plus the walking is weird with the cbm and the angled heel steps. Sort of like walking sideways. This dance demands being taught by someone that really knows what they are doing. I did Tango incorrectly for about 4 years.