Does anyone upload to Second Life from Blender? I have rigged and weighted an object for the company I work for. It works perfectly in Blender.

I have several issues below in which I have no idea what is going wrong. If anyone has had this happen when they've taken things out of Blender and have some sort of answer for WHY they are happening, I would like some feedback. There are so many questions for so many issues. I understand this site does not provide tutorials. That is not what I asked for. I asked if anyone else has uploaded from Blender to Second Life, if so, have they encountered any of the issues below, if so, how did they fix them?

However, in Second Life, we have had an array of issues:

Too high of a vertex count (we reduced the vertices)
Second Life didn't like the triangles on the object and added faces that we didn't want (we removed all the triangles)

My mirrored object showed up as two left feet instead of a right and a left (so far, the most recent haven't done that and I'm not sure what we did differently to fix that.)

The feet were aligned, texture applied correctly, one of each foot, but when you click edit in Second Life, it flings the Avatar really far away. (No solution yet to this.)

And most recently, the aligned, mirrored, rigged and weighted feet are costing 11 prims, which is perfect, but they turn the Second Life avatar that wears the feet to look like a Frankenstein mishap. The feet seem to attach the avatar from blender with the feet to the avatar in Second Life, when all I'm doing is exporting the feet. I only select the feet and it didn't do this with previous versions of the feet. I have no idea what I'm doing wrong and am grasping at straws.

So I'm looking to find someone who might be able to walk me through what I'm doing wrong or have some sort of insight as to something else I could try. I have spent countless hours on these feet and after two weeks, haven't completed ONE project for my boss. I need a Second Life/Blender sensei. =)
I have now successfully answered all of the questions to all of the issues I was having previously!

Too high vertex count - reduced

Small triangles that added material upon import into Second Life - removed

Mirrored object showing two left feet - still unsure how this one fixed itself

Avatar being offset (flung) along the Z axis - upon import into SL, don't include joint positions

Frankenstein mishap, click only feet, export, manually choose the default settings for rigged open sim instead of choosing the automatic one, not sure why.

I may have graduated from Grasshopper level Blender user!