#pd1ds, #ZacD
Thank you for your inputs, and sorry for taking so long about my response. several days away from my computer, I will take your Notes.
at the time of writing ( Nov 11, 2016 ), I’m still in the process of learning related Software with Trials-and-Errors
1.) still learning Blender but not only for Modelling, gets more confident and comfort to
2.) finished the first 3 Official Tutorial Videos of Substance Designer - Getting Started,
this software tool makes sense, however I will put SD on the shelf and leave it for a while, might back to it later. ( my priority is to know all related Workflow )
3.) learning Substance Painter, Just beginning and feel its good to go 
For my Updates :
Now, I’ve successfully exported FBX File from Blender, and then
imported to UE4 (for Testing that I should not get errors when building)
–> I got 2 errors about Object has overlapping UVs and Lightmap UV are overlapping x%…, that’s the common problem for noob like me, and google has solutions.
They have separated Root Causes,
the 1st Problem : when importing the FBX File to UE4, you will have to uncheck “Combine Mesh” in the Import Options of UE4 ( if a Single Model consists of multiple Mesh Objects, or imagine that the Model is Assembly )
the 2nd Problem : in Blender, just click the ‘+’ in Object Data > UV Maps ( assume that you already have an unwrapped UV for Texture ) to add another one as the 2nd UV Channel for UE4 Lightmap,
and when importing the FBX File to UE4, you will have to uncheck “Generate Lightmap UVs”.
imported to SP (to be used for learning with SP Tutorial)
–> you will need to separate the Model into Parts or Sections(perform in Blender), and assign the different Material_ID to each Part or Section(perform in Blender), for Painting Process in Substance Painter.
my Hint :
you may not be able to solve the problem from a tutorial you’ve just found,
but you may need to learn from some/many tutorials to get a thing done.
and you may need to adapt your knowledge/technic from one to another situation during the time you’re learning.
For my Initial Questions :
at the time of writing ( Nov 11, 2016 ), I’m still in the process of learning related Software with Trials-and-Errors
may be a month or a few months later, when I have the complete picture in my head,
I will come back to answer or share what I have.
if someone facing troubles related to this Thread, hope I or someone could help you in someway, just leave your question here.
Thank you very much for your interesting and supports