No, you cannot. Do not nest a shortcode inside the same shortcode. So, do not put a Row shortocode inside another Row shortcode. Also, do not make use at all of deep nesting: a Row which is inside Columns which is inside another Row.

However, you could nest shortcodes of different types: a Column inside a Row and viceversa. Or, you could nest a Button inside a Row, even if the reverse is not possible. Why? Because Basic Shortcodes do not allow nesting inside them of other shortcodes at all.

When entering margins, borders or paddings, you should always keep in mind the same order of sides – top, right, bottom and left, not otherwise.

Even if you need to insert just a single value. Let’s say you want to enter a value for bottom side, for example — 50 pixels. In this case, you need to enter all the values, as follows: 0px 0px 50px 0px, where px = pixels. You should always put “px” after each value you enter (even if they are 0), followed by space.

You are allowed to use negative values just for margins and position. However, when entering margins with negative values to elements like Row or Custom content shortcodes, you should always keep in mind that if you add a negative value to a side, you should add the same value to the opposite side, but – this time – the positive one. This is necessary to move the entire element at once.

For example, if you add -70px to right side, you should add 70px to the left side. So, you will insert in Margins box the following: 0px -70px 0px 70px.

Keep in mind that, in case you do not add the positive value to opposite side, the elements where applied will become taller or wider.

If comparing to Margins, the Position values — of both Row and Custom content shortcodes — do not affect the surrounding elements. If moving content with Position values instead of Margins values, the surrounding content will stay on its position. If moving with Margins, the content will flow nearby the moved content.