FSX-P3D-XP11-AFS2-DCS - in search for best practices for model multiplatform development.

In the past few weeks I have spent some time experimenting with DCS and XP11, along with Aerofly FS2 (for which I had already posted some screenshots of the S-211). Trying to convert my planes for these platforms showed the restrictions you need to take in account if you wanted to convert an FSX/P3D model to other platforms...and it is MUCH easier if you plan ahead and build your models in a certain way. Note that, after all these years, FSX/P3D SDK is, in many ways, still the most flexible in terms of modeling.

Being an engineer I felt the need to put my findings in an Excel spreadsheet - with the main scope of drawing some conclusions on what are these best practices and I planned to share them publicly in a proper format and with extensive explaination...but I'll never have the time to do that so here is the spreadsheet - color coded of course:

Green means no issues 
Yellow means "caution - some limitations or annoyances!"
Red means "warning - major problems or very cumbersome procedure!
Blue means "very cool"

Note that this is not a comparison of the simulators or the engines - just some personal observations from the aicraft modeling perspective - so do not get upset if you thing your simulator of choice is being overly criticized.
Note also that there is no commonality of any kind in the flight modeling between these platforms - so, apart from getting data and test points, you will have to redo each flight model in any case.

Resulting best pratices for this analysis are as follows:

• The preferred modeling software is 3D Studio MAX (surprise surprise)
• DO NOT use multimaterial in 3DS Max. FSX/P3D and DCS are fine with multimaterials, but AFS2 and XP11 are not.
• Use only SQUARE bitmaps if at all possible (actually only AFS2 does not support rectangular bitmaps...you can easily make them "square" by resizing them but it is a loss of resources (or resolution if you downsize them). And anyway this is a good practice in general for videogames over multiple engines.
• Make sure you do not have overlapping edges or vertices in the UVW coordinates. These will create artifacts in AFS2 (and to a lesser extent in XP11). This one too is a general good practice...but FSX and P3D tolerate it very well and there are no visual artifacts of sorts. 
• All the objects with hierarchy links MUST be done with the same material (this is a limitation which applies ONLY to XP11, but it is annoying). This is pretty imporant. If you have multiple parts that need to move together or ar part of a hierarchy chain they must be done with the same material. 
• Building analog instruments in 3D is preferred over dynamic textures. 3D animations of instruments and needles are supported in all of the platforms (and actually it is the way they are meant to be done in AFS2 in any case).
• Virtual cockpit must match the external model closely. While in FSX/P3D the VC is a completely separate model, in the other sims it is not like that. XP11 can have a "cockpit" object, but it is limited to one normal texture and one dynamic texture. DCS has a sepaarate VC model, true, but it superimposed on the external model geometry (and then you need to hide the elements you do not want). AFS seems to embrace the "unique model" philosophy - no separate VC model (but you can hide stuff from the external model, such as pilot figures).

I am sorry I do not have the time right now to go into further details… but still I hope it is useful.
I urge FSX/P3D designers to have a close look a XP11 as the conversion (at least for GA planes) is much simpler than it looks at a glance, and you can have your planes Flying in XP11 in days.
One one about Aerofly FS2 - I still think it has a lot of potential… but it needs a graphical tool to help plane developers. Conversion of the model is easy...but you have to animate it manually by entering axis, rotations and translations manually in a text file. It is doable, and you get used to it, but a graphical tool or a conversion of the animations from the modeling tool would be much much better.