I am looking for options to convert AutoCAD to microstation retraining the drawing properties like blocks in AutoCAD are editable blocks in microstation, line and text properties in AutoCAD are retained in micro station.
can you provide more details what do you mean by "AutoCAD properties"? It's too general.
DWG block are converted to cells with tags or ItemTypes (depending on MicroStation version and conversion setting), also it's not clear what line and text properties cannot be changed.
In fact, it seems to me more like normal question that should be discussed in MicroStation forum than like an idea for enhancement. Moreover, this is MicroStation Programming community, not users community.