Theory #1

[Innominate]

I didn't see a door either.  I'll put it on the list of things to check.

I've already posted that there is no alternative door. It was a mistaken interpretation of a comment in a document.

SIL has confirmed there is no alternative short cut entrance from the passageway.

[Robittybob1]

I've already posted that there is no alternative door. It was a mistaken interpretation of a comment in a document.

SIL has confirmed there is no alternative short cut entrance from the passageway.

Either way I'm going to check for myself.

[Alice Purjorick]

Correction.
2. The front door is open to an unknown angle.

Not to worry, Alice. If the skeleton had been found in the cupboard we could argue over how it got there & the contents of the autopsy report.
It's just trying to piece together a sequence of questionable events to reach the conclusion defined in the OP theory. At least this gives you the opportunity to link to backing music of your choice.

Plot it out on this:
http://www.gerrymccannsblogs.co.uk/press/14-May8/image001.jpg

This more my bag for backing music:
https://www.youtube.com/watch?v=FHKyVJ5YfNU

[Innominate]

The following link gives an indication of some of the possibilities for wind flow in a building:

https://sustainabilityworkshop.autodesk.com/buildings/wind-ventilation

[Brietta]

The following link gives an indication of some of the possibilities for wind flow in a building:

https://sustainabilityworkshop.autodesk.com/buildings/wind-ventilation

Do you think this had been taken into consideration in the design of the building?  It is a hot climate after all and would make sense to me.

[Alice Purjorick]

https://www.ncbi.nlm.nih.gov/books/NBK143285/

4.1.1. Wind pressure

When wind strikes a building, it induces a positive pressure on the windward face and negative pressure on the leeward face. This drives the air to flow through windward openings into the building to the low-pressure openings at the leeward face (see Figure 4.1). It is possible to estimate the wind pressures for simple buildings. Wind flows around buildings are complex and the subject of a number of textbooks, for example Aynsley, Melbourne & Vickery (1977) and Liu (1991).

[misty]

https://www.ncbi.nlm.nih.gov/books/NBK143285/

4.1.1. Wind pressure

When wind strikes a building, it induces a positive pressure on the windward face and negative pressure on the leeward face. This drives the air to flow through windward openings into the building to the low-pressure openings at the leeward face (see Figure 4.1). It is possible to estimate the wind pressures for simple buildings. Wind flows around buildings are complex and the subject of a number of textbooks, for example Aynsley, Melbourne & Vickery (1977) and Liu (1991).

Well I'm still not convinced as there were 2 openings on the windward side & one on the leeward side of 5A. Coupled with the fact that the wind did not enter at 90°, thus reducing its force, & 2 of the openings had curtains across them, I consider the front door would have had been the optimum opening for wind pressure.
Can we move on to the reasons why Madeleine would have exited by the front door, please?

[Robittybob1]

Well I'm still not convinced as there were 2 openings on the windward side & one on the leeward side of 5A. Coupled with the fact that the wind did not enter at 90°, thus reducing its force, & 2 of the openings had curtains across them, I consider the front door would have had been the optimum opening for wind pressure.
Can we move on to the reasons why Madeleine would have exited by the front door, please?

Only if the front door was open Misty. 
"reasons why Madeleine would have exited by the front door":
1.  Someone unknown moving near the patio door is my favourite.

[Innominate]

Well I'm still not convinced as there were 2 openings on the windward side & one on the leeward side of 5A. Coupled with the fact that the wind did not enter at 90°, thus reducing its force, & 2 of the openings had curtains across them, I consider the front door would have had been the optimum opening for wind pressure.
Can we move on to the reasons why Madeleine would have exited by the front door, please?

If you ever obtain raw data from Praia da Luz we can analyse it by assigning the observations to bins based on the compass sectors. By that method the variability of the wind direction will be clear.

Otherwise it like saying the average person is 1.8m tall without providing a standard deviation to allow someone to assess the spread.

Moving on. I have suggested a possible reason that MBM may have left the apartment was to find her parents; it is not possible to be certain either way on this point IMO.

[Innominate]

If you ever obtain raw data from Praia da Luz we can analyse it by assigning the observations to bins based on the compass sectors. By that method the variability of the wind direction will be clear.

Otherwise it like saying the average person is 1.8m tall without providing a standard deviation to allow someone to assess the spread.

A few videos of may help to illustrate the above point:

https://www.gettyimages.co.uk/license/503881678

https://www.gettyimages.co.uk/license/473066513

https://www.gettyimages.co.uk/detail/video/shot-of-automated-weather-observation-station-with-stock-video-footage/184159281

[Robittybob1]

If you ever obtain raw data from Praia da Luz we can analyse it by assigning the observations to bins based on the compass sectors. By that method the variability of the wind direction will be clear.

Otherwise it like saying the average person is 1.8m tall without providing a standard deviation to allow someone to assess the spread.

Moving on. I have suggested a possible reason that MBM may have left the apartment was to find her parents; it is not possible to be certain either way on this point IMO.

She can't exit both doors at once, so you have to think like as kid and understand why she would choose one door over the other.

[jassi]

She can't exit both doors at once, so you have to think like as kid and understand why she would choose one door over the other.

Yes, if she was disturbed by someone fiddling with the bedroom window then she is hardly likely to try ans exit by the door adjacent to that window

[Robittybob1]

Yes, if she was disturbed by someone fiddling with the bedroom window then she is hardly likely to try ans exit by the door adjacent to that window

Well that is right.  So can you accept that even though the opening of the shutters and window may have woken Madeleine, I think you have to be awake to become conscious of direction of sound.  So the alleged burglars may have stopped once it was note Madeleine woke.  So in this scenario she has woken unaware of where the sound has come from.

[jassi]

Well that is right.  So can you accept that even though the opening of the shutters and window may have woken Madeleine, I think you have to be awake to become conscious of direction of sound.  So the alleged burglars may have stopped once it was note Madeleine woke.  So in this scenario she has woken unaware of where the sound has come from.

No, I think the burglar stuff is just a load of guff.

[Robittybob1]

No, I think the burglar stuff is just a load of guff.

The point of discussing possibilities is not to dismiss them like that.