Converting Linestyles from DGN files Microstation to DWG

Active linestylescale (LTSCALE in AutoCAD terms) should be set to 1

Set Line Code Scale to 0.0 in DWG Options. This is the confusing one, if this is set to 0.0, the linestyle used for the DWG drawing will be as it looks in Microstation. Therefore make sure you fit the view first before exporting.

Export to DWG

Linestyles will be set to the length based on the view in MicroStation.

Alternatively, remap linestyles to AutoCAD styles

Set LTSCALE to the scale of the drawing