Beams correctly connected?

I want achieve this result: 3/4 measure, with 6 eighth notes connected in the Second voice.

So: open this file: test file_1.mscz

1) Select the second measure
2) For the example: in the Beam Properties palette, double-click on the first symbol (beam start) or the third (single note), see following image

Result, as expected:

3) Now, repeat the same operation (select second measure) -> double-click on the second sign (beam medium)

Result.
Correct or not?

The expected result would be rather this one?

4) Finally, select all: Ctrl + A
When you make double-click on the first or the third sign: result OK

If you Select All -> double-click on the second sign, you receive this. What do you think about this?

EDIT: I know that it works (for the first image-example) if I select the third and the fifth 8th, then double-click on the second sign.