Is there anyone who has a solution to "Run through corners" ?

I was a little unclear, this also applies when I save my file as a DGN-file. When I open the DGN-file again, it has lost the "run through corners" setting.

Why does not the settings remain, that is my question.

We constantly receive feedback / comment that the customer wants lines that flow through the entire line, not broken at the insert points / breaking points.

Anyone have any solution? 

When file is opened in DWG workmode then lines are automatically saved with DWG compatibility(adjustment auto) so even saved in DGN it loses option trough corners. In v8 DGN format there are two options either linestyle is linked from RSC files(v7) or linestyle and it's symbols is embedded in file.

But some example files would be good to look into.

Where are these linestyles defined?
Are you working on DWG files, DGN files, or are you working with some other software package altogether? What version of your software are you using?

Are you creating these files with something that isn't MicroStation or AutoCAD, but expecting the drawings to display the same way as they do in your host software?

I create a new dgn-file, then I do some mapping, then I export to dwg.

The line styles that I use is not MS standards, they come from rcs-files or shx files. 

Once again, the problem: I think its strange when I use the "run through corners" setting it all look good in the View, But when I do an export to dwg and open that file the settings are gone. And the same happens to the original dgn-file if I close it and the open it agian, the setting are gone. 

For DWG it is expected as in DWG only one method is available "Shift: Centered". But this is not expected to change if using DGN only. Also it is suspicious that you mention using SHX files as these contain linetype symbols so if line is created using symbols then symbols can't break and "run trough corners". Keep in mind that if you export DGN to DWG without using Remap table then MS automatically creates a shx file in RSC output directory from MS linestyles and it may not look the same when opened in AutoCAD.

Unfortunately using Remap table still is a must to keep linestyles standartized and also it is best to have linestyles symbols to have same name in RSC and SHX.