Why is the drawing of this box default 2mm and the other is 5mm.

Hi @dublove ,

I see something special. The default stroke weight in your provided document is 0.1 mm instead of 1 Pt.

At one point the default object style was changed…

Hm.

Maybe we see something different if you'd provide the corresponding InDesign document and not an exported IDML file.

Regards,
Uwe Laubender
( Adobe Community Expert )

Additional I have to remark, that if you save a file as IDML the tool defaults get lost. So we are not able to see irregularities with your tools as we don't get this information. If you experience problems with your program behaviors, use theIDML file. 

I don't see any abnormality. InDesign uses the settings what you make when no tool is selected.

If you want to have specific setting , make an object style and move the default proxy for graphic frames to that style, do the same with the proxy for text frames.

I don't understand the issue - I looked at the file - seems to be working as normal. 

What's going on? Can you please clarify?